diff --git a/electrum/address_synchronizer.py b/electrum/address_synchronizer.py
index 3e490f8f4..0b8578213 100644
--- a/electrum/address_synchronizer.py
+++ b/electrum/address_synchronizer.py
@@ -787,7 +787,7 @@ class AddressSynchronizer(Logger, EventListener):
         self.db.add_num_inputs_to_tx(txid, len(tx.inputs()))
         return fee
 
-    def get_addr_io(self, address):
+    def get_addr_io(self, address: str):
         with self.lock, self.transaction_lock:
             h = self.get_address_history(address).items()
             received = {}
diff --git a/electrum/wallet.py b/electrum/wallet.py
index 3b6485999..b1db5f61e 100644
--- a/electrum/wallet.py
+++ b/electrum/wallet.py
@@ -922,6 +922,8 @@ class Abstract_Wallet(ABC, Logger, EventListener):
                 parents.append(_txid)
                 # detect address reuse
                 addr = self.adb.get_txin_address(txin)
+                if addr is None:
+                    continue
                 received, sent = self.adb.get_addr_io(addr)
                 if len(sent) > 1:
                     my_txid, my_height, my_pos = sent[txin.prevout.to_str()]