diff --git a/app/src/main/java/com/tangem/tap/ApplicationEntryPoint.kt b/app/src/main/java/com/tangem/tap/ApplicationEntryPoint.kt
index d28fb50cbc..f39b16e9d7 100644
--- a/app/src/main/java/com/tangem/tap/ApplicationEntryPoint.kt
+++ b/app/src/main/java/com/tangem/tap/ApplicationEntryPoint.kt
@@ -2,7 +2,7 @@ package com.tangem.tap
 
 import com.tangem.TangemSdkLogger
 import com.tangem.blockchainsdk.BlockchainSDKFactory
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
 import com.tangem.blockchainsdk.utils.ExcludedBlockchains
 import com.tangem.common.routing.AppRouter
 import com.tangem.core.analytics.filter.OneTimeEventFilter
diff --git a/app/src/main/java/com/tangem/tap/TangemApplication.kt b/app/src/main/java/com/tangem/tap/TangemApplication.kt
index c8408c6e91..e8323470e3 100644
--- a/app/src/main/java/com/tangem/tap/TangemApplication.kt
+++ b/app/src/main/java/com/tangem/tap/TangemApplication.kt
@@ -8,7 +8,7 @@ import com.tangem.Log
 import com.tangem.TangemSdkLogger
 import com.tangem.blockchain.network.BlockchainSdkRetrofitBuilder
 import com.tangem.blockchainsdk.BlockchainSDKFactory
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
 import com.tangem.blockchainsdk.utils.ExcludedBlockchains
 import com.tangem.common.routing.AppRouter
 import com.tangem.core.analytics.Analytics
diff --git a/app/src/main/java/com/tangem/tap/common/libs/blockchainsdk/DefaultTransactionSignerFactory.kt b/app/src/main/java/com/tangem/tap/common/libs/blockchainsdk/DefaultTransactionSignerFactory.kt
index edd0ded835..e31c519069 100644
--- a/app/src/main/java/com/tangem/tap/common/libs/blockchainsdk/DefaultTransactionSignerFactory.kt
+++ b/app/src/main/java/com/tangem/tap/common/libs/blockchainsdk/DefaultTransactionSignerFactory.kt
@@ -3,18 +3,20 @@ package com.tangem.tap.common.libs.blockchainsdk
 import com.tangem.Message
 import com.tangem.TangemSdk
 import com.tangem.blockchain.common.TransactionSigner
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
+import com.tangem.domain.card.models.TwinKey
 import com.tangem.tap.common.redux.global.GlobalAction
 import com.tangem.tap.domain.TangemSigner
 import com.tangem.tap.store
 
 internal class DefaultTransactionSignerFactory : TransactionSignerFactory {
 
-    override fun createTransactionSigner(cardId: String?, sdk: TangemSdk): TransactionSigner {
+    override fun createTransactionSigner(cardId: String?, sdk: TangemSdk, twinKey: TwinKey?): TransactionSigner {
         return TangemSigner(
             cardId = cardId,
             tangemSdk = sdk,
             initialMessage = Message(),
+            twinKey = twinKey,
         ) { signResponse ->
             store.dispatch(action = GlobalAction.IsSignWithRing(signResponse.isRing))
         }
diff --git a/app/src/main/java/com/tangem/tap/di/libs/blockchainsdk/TransactionSignerFactoryModule.kt b/app/src/main/java/com/tangem/tap/di/libs/blockchainsdk/TransactionSignerFactoryModule.kt
index 36bc5ce13a..d0997c9038 100644
--- a/app/src/main/java/com/tangem/tap/di/libs/blockchainsdk/TransactionSignerFactoryModule.kt
+++ b/app/src/main/java/com/tangem/tap/di/libs/blockchainsdk/TransactionSignerFactoryModule.kt
@@ -1,6 +1,6 @@
 package com.tangem.tap.di.libs.blockchainsdk
 
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
 import com.tangem.tap.common.libs.blockchainsdk.DefaultTransactionSignerFactory
 import dagger.Module
 import dagger.Provides
diff --git a/app/src/main/java/com/tangem/tap/domain/TangemSigner.kt b/app/src/main/java/com/tangem/tap/domain/TangemSigner.kt
index f53d9d0736..7f5f095079 100644
--- a/app/src/main/java/com/tangem/tap/domain/TangemSigner.kt
+++ b/app/src/main/java/com/tangem/tap/domain/TangemSigner.kt
@@ -5,6 +5,7 @@ import com.tangem.TangemSdk
 import com.tangem.blockchain.common.TransactionSigner
 import com.tangem.blockchain.common.Wallet
 import com.tangem.common.CompletionResult
+import com.tangem.domain.card.models.TwinKey
 import com.tangem.domain.models.scan.isRing
 import com.tangem.tap.domain.tasks.SignHashesTask
 import kotlinx.coroutines.suspendCancellableCoroutine
@@ -14,6 +15,7 @@ class TangemSigner(
     private val cardId: String?,
     private val tangemSdk: TangemSdk,
     private val initialMessage: Message,
+    private val twinKey: TwinKey?,
     private val signerCallback: (TangemSignerResponse) -> Unit,
 ) : TransactionSigner {
 
@@ -22,7 +24,7 @@ class TangemSigner(
         publicKey: Wallet.PublicKey,
     ): CompletionResult<List<ByteArray>> {
         return suspendCancellableCoroutine { continuation ->
-            val task = SignHashesTask(hashes, publicKey)
+            val task = SignHashesTask(hashes, publicKey, twinKey?.getPairKey(publicKey.seedKey))
 
             tangemSdk.startSessionWithRunnable(
                 runnable = task,
diff --git a/app/src/main/java/com/tangem/tap/domain/tasks/SignHashesTask.kt b/app/src/main/java/com/tangem/tap/domain/tasks/SignHashesTask.kt
index e5616aacd7..8d637b7c78 100644
--- a/app/src/main/java/com/tangem/tap/domain/tasks/SignHashesTask.kt
+++ b/app/src/main/java/com/tangem/tap/domain/tasks/SignHashesTask.kt
@@ -5,6 +5,8 @@ import com.tangem.common.CompletionResult
 import com.tangem.common.core.CardSession
 import com.tangem.common.core.CardSessionRunnable
 import com.tangem.common.core.CompletionCallback
+import com.tangem.common.core.TangemSdkError
+import com.tangem.crypto.hdWallet.DerivationPath
 import com.tangem.operations.CommandResponse
 import com.tangem.operations.sign.SignHashesCommand
 
@@ -18,7 +20,9 @@ class TangemSignHashesResponse(
 class SignHashesTask(
     private val hashes: Collection<ByteArray>,
     private val publicKey: Wallet.PublicKey,
+    private val pairWalletPublicKey: ByteArray?,
 ) : CardSessionRunnable<TangemSignHashesResponse> {
+
     override fun run(session: CardSession, callback: CompletionCallback<TangemSignHashesResponse>) {
         SignHashesCommand(hashes.toTypedArray(), publicKey.seedKey, publicKey.derivationPath).run(session) { response ->
             when (response) {
@@ -35,8 +39,42 @@ class SignHashesTask(
                         ),
                     )
                 }
-                is CompletionResult.Failure ->
+                is CompletionResult.Failure -> {
+                    when {
+                        response.error is TangemSdkError.WalletNotFound && pairWalletPublicKey != null -> {
+                            sign(session, pairWalletPublicKey, publicKey.derivationPath, callback)
+                        }
+                        else -> callback(CompletionResult.Failure(response.error))
+                    }
+                }
+            }
+        }
+    }
+
+    private fun sign(
+        session: CardSession,
+        publicKey: ByteArray,
+        derivationPath: DerivationPath?,
+        callback: CompletionCallback<TangemSignHashesResponse>,
+    ) {
+        SignHashesCommand(hashes.toTypedArray(), publicKey, derivationPath).run(session) { response ->
+            when (response) {
+                is CompletionResult.Success -> {
+                    val card = session.environment.card
+                    callback(
+                        CompletionResult.Success(
+                            TangemSignHashesResponse(
+                                signatures = response.data.signatures,
+                                totalSignedHashes = response.data.totalSignedHashes,
+                                remainingSignatures = card?.wallet(publicKey)?.remainingSignatures,
+                                batchId = card?.batchId,
+                            ),
+                        ),
+                    )
+                }
+                is CompletionResult.Failure -> {
                     callback(CompletionResult.Failure(response.error))
+                }
             }
         }
     }
diff --git a/app/src/main/java/com/tangem/tap/domain/walletconnect/WalletConnectSdkHelper.kt b/app/src/main/java/com/tangem/tap/domain/walletconnect/WalletConnectSdkHelper.kt
index 17fb4389ab..736b070b7a 100644
--- a/app/src/main/java/com/tangem/tap/domain/walletconnect/WalletConnectSdkHelper.kt
+++ b/app/src/main/java/com/tangem/tap/domain/walletconnect/WalletConnectSdkHelper.kt
@@ -218,6 +218,7 @@ class WalletConnectSdkHelper {
             signer = store.inject(DaggerGraphState::transactionSignerFactory).createTransactionSigner(
                 cardId = cardId,
                 sdk = sdk,
+                twinKey = null, // use null here because twin doesn't support WC
             ),
         )
         return when (result) {
diff --git a/app/src/main/java/com/tangem/tap/network/exchangeServices/CurrencyExchangeManager.kt b/app/src/main/java/com/tangem/tap/network/exchangeServices/CurrencyExchangeManager.kt
index 6504558f4f..b117321609 100644
--- a/app/src/main/java/com/tangem/tap/network/exchangeServices/CurrencyExchangeManager.kt
+++ b/app/src/main/java/com/tangem/tap/network/exchangeServices/CurrencyExchangeManager.kt
@@ -104,6 +104,7 @@ class CurrencyExchangeManager(
     }
 }
 
+@Deprecated("Useless")
 suspend fun buyErc20TestnetTokens(card: CardDTO, walletManager: EthereumWalletManager, destinationAddress: String) {
     walletManager.safeUpdate(card.isDemoCard())
 
@@ -123,6 +124,7 @@ suspend fun buyErc20TestnetTokens(card: CardDTO, walletManager: EthereumWalletMa
         cardId = card.cardId.takeIf { isCardNotBackedUp },
         tangemSdk = store.inject(DaggerGraphState::cardSdkConfigRepository).sdk,
         initialMessage = Message(),
+        twinKey = null,
     ) { signResponse ->
         store.dispatch(
             GlobalAction.UpdateWalletSignedHashes(
diff --git a/app/src/main/java/com/tangem/tap/proxy/redux/DaggerGraphState.kt b/app/src/main/java/com/tangem/tap/proxy/redux/DaggerGraphState.kt
index bd75d53d4e..2333f95cf5 100644
--- a/app/src/main/java/com/tangem/tap/proxy/redux/DaggerGraphState.kt
+++ b/app/src/main/java/com/tangem/tap/proxy/redux/DaggerGraphState.kt
@@ -1,7 +1,7 @@
 package com.tangem.tap.proxy.redux
 
 import com.tangem.blockchainsdk.BlockchainSDKFactory
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
 import com.tangem.blockchainsdk.utils.ExcludedBlockchains
 import com.tangem.common.routing.AppRouter
 import com.tangem.core.decompose.ui.UiMessageSender
diff --git a/data/card/src/main/java/com/tangem/data/card/DefaultCardSdkConfigRepository.kt b/data/card/src/main/java/com/tangem/data/card/DefaultCardSdkConfigRepository.kt
index e4006b694a..84aa2bcf9e 100644
--- a/data/card/src/main/java/com/tangem/data/card/DefaultCardSdkConfigRepository.kt
+++ b/data/card/src/main/java/com/tangem/data/card/DefaultCardSdkConfigRepository.kt
@@ -2,12 +2,12 @@ package com.tangem.data.card
 
 import com.tangem.TangemSdk
 import com.tangem.blockchain.common.TransactionSigner
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
 import com.tangem.common.UserCodeType
 import com.tangem.common.core.CardIdDisplayFormat
 import com.tangem.common.core.UserCodeRequestPolicy
 import com.tangem.data.card.sdk.CardSdkProvider
 import com.tangem.domain.card.repository.CardSdkConfigRepository
+import com.tangem.domain.card.models.TwinKey
 import com.tangem.domain.models.scan.ProductType
 
 /**
@@ -61,8 +61,8 @@ internal class DefaultCardSdkConfigRepository(
         }
     }
 
-    override fun getCommonSigner(cardId: String?): TransactionSigner {
-        return transactionSignerFactory.createTransactionSigner(cardId = cardId, sdk = sdk)
+    override fun getCommonSigner(cardId: String?, twinKey: TwinKey?): TransactionSigner {
+        return transactionSignerFactory.createTransactionSigner(cardId = cardId, sdk = sdk, twinKey = twinKey)
     }
 
     override fun isLinkedTerminal() = sdk.config.linkedTerminal
diff --git a/data/card/src/main/java/com/tangem/data/card/TransactionSignerFactory.kt b/data/card/src/main/java/com/tangem/data/card/TransactionSignerFactory.kt
new file mode 100644
index 0000000000..4da2cdf41c
--- /dev/null
+++ b/data/card/src/main/java/com/tangem/data/card/TransactionSignerFactory.kt
@@ -0,0 +1,13 @@
+package com.tangem.data.card
+
+import com.tangem.TangemSdk
+import com.tangem.blockchain.common.TransactionSigner
+import com.tangem.domain.card.models.TwinKey
+
+/**
+[REDACTED_AUTHOR]
+ */
+interface TransactionSignerFactory {
+
+    fun createTransactionSigner(cardId: String?, sdk: TangemSdk, twinKey: TwinKey?): TransactionSigner
+}
\ No newline at end of file
diff --git a/data/card/src/main/java/com/tangem/data/card/di/CardDataModule.kt b/data/card/src/main/java/com/tangem/data/card/di/CardDataModule.kt
index cfdd7984b5..278ec54ba3 100644
--- a/data/card/src/main/java/com/tangem/data/card/di/CardDataModule.kt
+++ b/data/card/src/main/java/com/tangem/data/card/di/CardDataModule.kt
@@ -1,6 +1,6 @@
 package com.tangem.data.card.di
 
-import com.tangem.blockchainsdk.signer.TransactionSignerFactory
+import com.tangem.data.card.TransactionSignerFactory
 import com.tangem.data.card.DefaultCardRepository
 import com.tangem.data.card.DefaultCardSdkConfigRepository
 import com.tangem.data.card.sdk.CardSdkProvider
diff --git a/domain/card/src/main/kotlin/com/tangem/domain/card/models/TwinKey.kt b/domain/card/src/main/kotlin/com/tangem/domain/card/models/TwinKey.kt
new file mode 100644
index 0000000000..d105415c03
--- /dev/null
+++ b/domain/card/src/main/kotlin/com/tangem/domain/card/models/TwinKey.kt
@@ -0,0 +1,49 @@
+package com.tangem.domain.card.models
+
+import com.tangem.common.extensions.hexToBytes
+import com.tangem.domain.models.scan.ProductType
+import com.tangem.domain.models.scan.ScanResponse
+
+data class TwinKey(
+    val key1: ByteArray,
+    val key2: ByteArray,
+) {
+    fun getPairKey(walletPublicKey: ByteArray): ByteArray? {
+        return when {
+            walletPublicKey.contentEquals(key1) -> key2
+            walletPublicKey.contentEquals(key2) -> key1
+            else -> null
+        }
+    }
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (javaClass != other?.javaClass) return false
+
+        other as TwinKey
+
+        if (!key1.contentEquals(other.key1)) return false
+        if (!key2.contentEquals(other.key2)) return false
+
+        return true
+    }
+
+    override fun hashCode(): Int {
+        var result = key1.contentHashCode()
+        result = 31 * result + key2.contentHashCode()
+        return result
+    }
+
+    companion object {
+
+        fun getOrNull(scanResponse: ScanResponse): TwinKey? {
+            return if (scanResponse.productType == ProductType.Twins) {
+                val key1 = scanResponse.card.wallets.firstOrNull()?.publicKey ?: return null
+                val key2 = scanResponse.secondTwinPublicKey?.hexToBytes() ?: return null
+                TwinKey(key1 = key1, key2 = key2)
+            } else {
+                null
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/domain/card/src/main/kotlin/com/tangem/domain/card/repository/CardSdkConfigRepository.kt b/domain/card/src/main/kotlin/com/tangem/domain/card/repository/CardSdkConfigRepository.kt
index fd2f4e3b54..ecf06c78d8 100644
--- a/domain/card/src/main/kotlin/com/tangem/domain/card/repository/CardSdkConfigRepository.kt
+++ b/domain/card/src/main/kotlin/com/tangem/domain/card/repository/CardSdkConfigRepository.kt
@@ -2,6 +2,7 @@ package com.tangem.domain.card.repository
 
 import com.tangem.TangemSdk
 import com.tangem.blockchain.common.TransactionSigner
+import com.tangem.domain.card.models.TwinKey
 import com.tangem.domain.models.scan.ProductType
 
 /**
@@ -28,7 +29,7 @@ interface CardSdkConfigRepository {
     fun updateCardIdDisplayFormat(productType: ProductType)
 
     /** Get common signer by [cardId] */
-    fun getCommonSigner(cardId: String?): TransactionSigner
+    fun getCommonSigner(cardId: String?, twinKey: TwinKey?): TransactionSigner
 
     /** Check if linked terminal is enabled */
     fun isLinkedTerminal(): Boolean?
diff --git a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/AssociateAssetUseCase.kt b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/AssociateAssetUseCase.kt
index 979c1c911d..b910f1c01c 100644
--- a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/AssociateAssetUseCase.kt
+++ b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/AssociateAssetUseCase.kt
@@ -35,7 +35,10 @@ class AssociateAssetUseCase(
             if (isBalanceZero(userWalletId, networkCoin)) {
                 raise(AssociateAssetError.NotEnoughBalance(networkCoin))
             }
-            val signer = cardSdkConfigRepository.getCommonSigner(cardId = null)
+            val signer = cardSdkConfigRepository.getCommonSigner(
+                cardId = null,
+                twinKey = null, // use null here because no assets support for Twin cards
+            )
 
             catch(
                 block = {
diff --git a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/RetryIncompleteTransactionUseCase.kt b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/RetryIncompleteTransactionUseCase.kt
index 83467e5a33..ac7534976a 100644
--- a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/RetryIncompleteTransactionUseCase.kt
+++ b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/RetryIncompleteTransactionUseCase.kt
@@ -23,7 +23,10 @@ class RetryIncompleteTransactionUseCase(
         currency: CryptoCurrency,
     ): Either<IncompleteTransactionError, Unit> {
         return either {
-            val signer = cardSdkConfigRepository.getCommonSigner(cardId = null)
+            val signer = cardSdkConfigRepository.getCommonSigner(
+                cardId = null,
+                twinKey = null, // use null here because no assets support for Twin cards
+            )
 
             catch(
                 block = {
diff --git a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/SendTransactionUseCase.kt b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/SendTransactionUseCase.kt
index 59f1d6382f..c6fc973fc9 100644
--- a/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/SendTransactionUseCase.kt
+++ b/domain/transaction/src/main/java/com/tangem/domain/transaction/usecase/SendTransactionUseCase.kt
@@ -16,6 +16,7 @@ import com.tangem.domain.common.TapWorkarounds.isStart2Coin
 import com.tangem.domain.common.TapWorkarounds.isTangemTwins
 import com.tangem.domain.demo.DemoConfig
 import com.tangem.domain.demo.DemoTransactionSender
+import com.tangem.domain.card.models.TwinKey
 import com.tangem.domain.tokens.model.Network
 import com.tangem.domain.transaction.TransactionRepository
 import com.tangem.domain.transaction.error.SendTransactionError
@@ -37,7 +38,10 @@ class SendTransactionUseCase(
         val card = userWallet.scanResponse.card
         val isCardNotBackedUp = card.backupStatus?.isActive != true && !card.isTangemTwins
 
-        val signer = cardSdkConfigRepository.getCommonSigner(cardId = card.cardId.takeIf { isCardNotBackedUp })
+        val signer = cardSdkConfigRepository.getCommonSigner(
+            cardId = card.cardId.takeIf { isCardNotBackedUp },
+            twinKey = TwinKey.getOrNull(scanResponse = userWallet.scanResponse),
+        )
 
         val linkedTerminal = cardSdkConfigRepository.isLinkedTerminal()
         if (userWallet.scanResponse.card.isStart2Coin) {
diff --git a/libs/blockchain-sdk/src/main/java/com/tangem/blockchainsdk/signer/TransactionSignerFactory.kt b/libs/blockchain-sdk/src/main/java/com/tangem/blockchainsdk/signer/TransactionSignerFactory.kt
deleted file mode 100644
index da53a4d024..0000000000
--- a/libs/blockchain-sdk/src/main/java/com/tangem/blockchainsdk/signer/TransactionSignerFactory.kt
+++ /dev/null
@@ -1,12 +0,0 @@
-package com.tangem.blockchainsdk.signer
-
-import com.tangem.TangemSdk
-import com.tangem.blockchain.common.TransactionSigner
-
-/**
-[REDACTED_AUTHOR]
- */
-interface TransactionSignerFactory {
-
-    fun createTransactionSigner(cardId: String?, sdk: TangemSdk): TransactionSigner
-}
\ No newline at end of file