Updated on 2026-08-14

app/src/main/java/com/tangem/tap/domain/tasks/visa/VisaCardActivationTask.kt

@@ -363,7 +363,7 @@ class VisaCardActivationTask @AssistedInject constructor(
             signature = response.signature,
             hash = dataToSign.hashToSign.hexToBytes(),
             publicKey = derivedPublicKey.publicKey.toDecompressedPublicKey(),
-        ).asRSVLegacyEVM().toHexString()
+        ).asRSVLegacyEVM().toHexString().lowercase()
 
         val signedActivationData = dataToSign.sign(
             rootOTP = otp.rootOTP.toHexString(),

app/src/main/java/com/tangem/tap/domain/tasks/visa/VisaCustomerWalletApproveTask.kt

@@ -181,7 +181,7 @@ class VisaCustomerWalletApproveTask(
                         hash = hashToSign,
                         publicKey = extendedPublicKey?.publicKey?.toDecompressedPublicKey()
                             ?: targetWalletPublicKey.toDecompressedPublicKey(),
-                    ).asRSVLegacyEVM().toHexString()
+                    ).asRSVLegacyEVM().toHexString().lowercase()
 
                     scanCard(
                         session = session,

app/src/main/java/com/tangem/tap/domain/walletconnect/WalletConnectSdkHelper.kt

@@ -393,7 +393,7 @@ class WalletConnectSdkHelper {
                         signature = signedHash,
                         hash = hashToSign,
                         publicKey = wallet.publicKey.blockchainKey.toDecompressedPublicKey(),
-                    ).asRSVLegacyEVM().toHexString()
+                    ).asRSVLegacyEVM().toHexString().lowercase() // use lowercase because some dapps cant handle UPPERCASE
                 }
             }
             is CompletionResult.Failure -> {