When I Bump Fee, tx amount also changing.

[y-vnk]

If I send 20$ with fee of 18$ to user "A", and I tried to bump fee to 40$. I am able to see change in amount (double the amount which i sent 40$) which I sent to user "A"

[y-vnk]

@BitcoinZavior
Can you please check and let me know anything else I need to implement or is there any issue from my end?
For Bumping fee, I am justing sending parameters feerate and txid.

` BumpFeeTxBuilder bumpFeeTxBuilder =
BumpFeeTxBuilder(txid: txid, feeRate: feeRate);

  bumpFeeTxBuilder.allowShrinking(address);
  bumpFeeTxBuilder.enableRbf();
  TxBuilderResult data = await bumpFeeTxBuilder.finish(wallet!);
  final response = await wallet.sign(psbt: data.psbt);

  String? bTxid = await broadcastTransaction(
    tx: PartiallySignedTransaction(psbtBase64: response.psbtBase64),
  );`

[BitcoinZavior]

I was able to replace a tx using bumpfee, it did not create another transaction as you mentioned above.

Here is my old tx, it shows the replaced by tx as well: https://mempool.space/testnet/tx/9e768566c5d55a0db37c0242000fe4d5124dd932438af67baf2c3d3f2f517842

Below is the code used:

sendBumpfeeTx(
     Blockchain blockchain, Wallet wallet, String address, String txid) async {
   try {
     final feeRate = await blockchain.estimateFee(25);
     final txBuilder =
         BumpFeeTxBuilder(txid: txid, feeRate: 5);
      txBuilder.enableRbf();
     TxBuilderResult data = await txBuilder.finish(wallet);
     final sbt = await wallet.sign(psbt: data.psbt);
     final tx = await sbt.extractTx();
     await blockchain.broadcast(tx);
   } on Exception {
     rethrow;
   }
 }

[BitcoinZavior]

Related to bitcoindevkit/bdk#1342