undo verified tx when swapping chains

lib/wallet.py

@@ -294,6 +294,10 @@ class Abstract_Wallet(PrintError):
         return self.get_pubkeys(*sequence)
 
     def add_unverified_tx(self, tx_hash, tx_height):
+        if tx_height == 0 and tx_hash in self.verified_tx:
+            self.verified_tx.pop(tx_hash)
+            self.verifier.merkle_roots.pop(tx_hash, None)
+
         # tx will be verified only if height > 0
         if tx_hash not in self.verified_tx:
             self.unverified_tx[tx_hash] = tx_height