<p>This probably means that you are trying to spend an UTxO that is already spent.</p>
<p>This can mean few things, but most probably that you are submitting the transaction for the second time.</p>
<p>If you are using Blockfrost, check the <code>/mempool</code> endpoint to see if you transaction is in the mempool or <code>/txs</code> if it is already on-chain.</p>

CC BY-SA 4.0
2022-12-06T21:04:05.720Z
It is on on-chain. So, what can I know from it? Can I ignore this error?
Heindrick
CC BY-SA 4.0
2022-12-06T21:21:26.017Z
Depending on your use case. Why are you getting this error in the first place? Are you trying to retry the transaction more times?
Marek Mahut - StakeNuts
CC BY-SA 4.0
2022-12-06T21:23:05.687Z
Yes. you are correct.
Heindrick
CC BY-SA 4.0
2022-12-06T21:31:27.397Z
In that case you can ignore the error. :)
Marek Mahut - StakeNuts
CC BY-SA 4.0
2022-12-06T21:33:11.490Z
Thank you. Could you explain in detail?
Heindrick
CC BY-SA 4.0
2022-12-06T21:34:41.853Z
The error just says that the utxo you are trying to spend is already spend, so you cannot do it again. Ideally, you would submit transaction once and check if it is in the mempool or txs and only if it is not there, you would resubmit ti again.
Marek Mahut - StakeNuts
CC BY-SA 4.0
2022-12-06T19:29:23.813Z
2022-12-06T19:29:23.813Z
Marek Mahut - StakeNuts
<p>I created transfer function with blockfrost.js and cardano-serialization-lib.</p>
<p>I refered following code.
<a href="https://github.com/blockfrost/blockfrost-js/tree/master/examples/simple-transaction" rel="nofollow noreferrer">https://github.com/blockfrost/blockfrost-js/tree/master/examples/simple-transaction</a></p>
<p>When I try to transfer with above code, I am getting following error.</p>
<pre><code>&quot;transaction submit error ShelleyTxValidationError ShelleyBasedEraBabbage (ApplyTxError [UtxowFailure (UtxoFailure (FromAlonzoUtxoFail (ValueNotConservedUTxO (Value 0 (fromList [])) (Value 2663366 (fromList []))))),UtxowFailure (UtxoFailure (FromAlonzoUtxoFail (BadInputsUTxO (fromList [TxIn (TxId {_unTxId = SafeHash \&quot;***\&quot;}) (TxIx 1)]))))])&quot;
</code></pre>
<p>Interesting thing is, transaction is success also, I can see success transaction in cardano explorer.</p>
<p>Can I ignore above error? Or how can I fix above error?</p>

CC BY-SA 4.0
2022-12-06T19:04:28.647Z
I think this error means you are spending a UTxO that is no longer available.
Christian Schmitz
<transaction><cardano-serialization-lib><blockfrost>
Transaction in Cardano
# Transaction in Cardano

(Asked by: username_0 on 2022-12-06)

I created transfer function with blockfrost.js and cardano-serialization-lib.
I refered following code.
https://github.com/blockfrost/blockfrost-js/tree/master/examples/simple-transaction
When I try to transfer with above code, I am getting following error.
"transaction submit error ShelleyTxValidationError ShelleyBasedEraBabbage (ApplyTxError [UtxowFailure (UtxoFailure (FromAlonzoUtxoFail (ValueNotConservedUTxO (Value 0 (fromList [])) (Value 2663366 (fromList []))))),UtxowFailure (UtxoFailure (FromAlonzoUtxoFail (BadInputsUTxO (fromList [TxIn (TxId {_unTxId = SafeHash \"***\"}) (TxIx 1)]))))])"

Interesting thing is, transaction is success also, I can see success transaction in cardano explorer.
Can I ignore above error? Or how can I fix above error?

**Tags:** transaction, cardano-serialization-lib, blockfrost
> **Comments:**
> **username_1**: I think this error means you are spending a UTxO that is no longer available.  

---

## 1 answers

### Answer by username_2 on 2022-12-06. Score: 2 | Accepted answer

This probably means that you are trying to spend an UTxO that is already spent.

This can mean few things, but most probably that you are submitting the transaction for the second time.

If you are using Blockfrost, check the `/mempool` endpoint to see if you transaction is in the mempool or `/txs` if it is already on-chain.

> **Comments:**
> **username_0**: It is on on-chain. So, what can I know from it? Can I ignore this error?  
> **username_2**: Depending on your use case. Why are you getting this error in the first place? Are you trying to retry the transaction more times?  
> **username_0**: Yes. you are correct.  
> **username_2**: In that case you can ignore the error. :)  
> **username_0**: Thank you. Could you explain in detail?  
> **username_2**: The error just says that the utxo you are trying to spend is already spend, so you cannot do it again. Ideally, you would submit transaction once and check if it is in the mempool or txs and only if it is not there, you would resubmit ti again.  

---

