[Question]: Mempool Conflict Error about bitcoinjs-lib HOT 2 CLOSED

From what I know, this message comes from the RPC node responding with the error message which says that the transaction being broadcasts conflicts with another transaction which exists in the mempool. This happens when your transaction attempts to use a UTXO that has already be included as an input for another transaction already broadcast; essentially a double spend.

The only way to fix this is with RBF.

from bitcoinjs-lib.

If this is intentional (You want to replace an already spent UTXO): Use RBF.

If this is unintentional: The place you are getting your UTXO information is bad, OR you are performing transactions too quickly for the API you're using while not accounting for self-spent UTXOs, so you're accidentally spending the same UTXO twice.

from bitcoinjs-lib.