testnet – Transactions solely work the primary time

I am implementing the code to signal and ship Bitcoin transactions on testnet, utilizing the bitcore library, in javascript.

I want some assist, as as soon as I attempt to broadcast my transaction, it provides me this error:

Error: txn-mempool-conflict

I’ve seen on-line that these are conflicts with one other transaction within the mempool, however I actually cannot discover any code examples on-line to have a look at. Can somebody assist me, giving me a sensible clarification of how I can do it? Any ideas and methods on the code are welcome.

Right here is the code:

async operate signAndSendTransaction(deal with, toAddress, quantity, addressPrivateKey) {
  attempt {
    const addressBalance = await getBalance(deal with);
    const toAddressBalance = await getBalance(toAddress);

    const amountInSatoshis = quantity * SATOSHIS_PER_BTC;
    const addressBalanceInSatoshi = addressBalance * SATOSHIS_PER_BTC;
    console.log("AMOUNT IN SATOSHI n" + amountInSatoshis);

    const toAddressBalanceInSatoshi = toAddressBalance * SATOSHIS_PER_BTC;

    console.log("BALANCE ADDRESS n" + addressBalanceInSatoshi);

    console.log("BALANCE TO-ADDRESS n" + toAddressBalanceInSatoshi);
    if (addressBalanceInSatoshi < amountInSatoshis) {
      console.log(`cannot ship ${quantity} BTC to ${deal with} beacuse the steadiness is lower than the tx quantity.`);
      return;
    }

    const utxos = (await axios.get(`https://api.bitcore.io/api/BTC/testnet/deal with/${deal with}/?unspent=true`)).knowledge;

    if (utxos.size === 0) {
      console.log(`There isn't any utxo for ${deal with}.`);
      return;
    }

    const unspentOutputs = utxos.map((utxo) => new bitcore.Transaction.UnspentOutput({
      txId: utxo.mintTxid,
      outputIndex: utxo.mintIndex,
      deal with: utxo.deal with,
      script: utxo.script,
      satoshis: utxo.worth,
    }));

    let tx = new bitcore.Transaction();
    console.log("n --------Unspent Outputs-------- n");
    console.log(unspentOutputs);
    console.log(tx);
    tx.from(unspentOutputs);
    tx.to(toAddress, amountInSatoshis);
    tx.change(deal with);

    const estimatedFee = tx.getFee();

    console.log(estimatedFee);
    tx.price(estimatedFee);

    // Non-public key of the desired public deal with that's sending BTC
    tx.signal(addressPrivateKey);

    console.log("n --------TX OBJECT-------- n");
    console.log(tx.toObject());

    const serializedTX = tx.serialize();
    console.log(serializedTX);

    const txid = (await axios.publish("https://api.bitcore.io/api/BTC/testnet/tx/ship", { rawTx: serializedTX })).knowledge;
    console.log(txid);
  } catch (error) {
    console.error(`Error: ${error.message}`);
  }
}