Update app.py

app.py

@@ -38,9 +38,10 @@ async def relay_txn(payload: dict):
     # Deserialize the transaction sent from the UI
     raw_tx = base58.b58decode(payload['txn'])
     txn = Transaction.from_bytes(raw_tx)
-    txn.sign([SERVER_KEY], txn.message.recent_blockhash)
+    txn.partial_sign([SERVER_KEY])
+
     partial_signed_bytes = bytes(txn)
-    encoded_txn = base58.b58encode(partial_signed_bytes).decode('utf-8')
+    encoded_txn = base58.b58encode(partial_signed_bytes).decode("utf-8")
 
     
     return {