diff --git a/src/main/java/com/sparrowwallet/drongo/wallet/FinalizingPSBTWallet.java b/src/main/java/com/sparrowwallet/drongo/wallet/FinalizingPSBTWallet.java
index 07df1f1..543bbe5 100644
--- a/src/main/java/com/sparrowwallet/drongo/wallet/FinalizingPSBTWallet.java
+++ b/src/main/java/com/sparrowwallet/drongo/wallet/FinalizingPSBTWallet.java
@@ -115,4 +115,9 @@ public class FinalizingPSBTWallet extends Wallet {
 
         return new Script(new byte[10]);
     }
+
+    @Override
+    public boolean canSign(PSBT psbt) {
+        return !getSigningNodes(psbt).isEmpty();
+    }
 }
\ No newline at end of file
diff --git a/src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java b/src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java
index 9e3f52b..e181280 100644
--- a/src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java
+++ b/src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java
@@ -578,7 +578,7 @@ public class Wallet {
     }
 
     public boolean canSign(PSBT psbt) {
-        return !getSigningNodes(psbt).isEmpty();
+        return isValid() && !getSigningNodes(psbt).isEmpty();
     }
 
     /**