bad-txns-inputs-missingorspent

[MitchDong]

We are having an issue with BTC withdrawal The customer withdraws via BTC, however the system wallet has insufficient funds. So we added some funds. After that, the customer tries to withdraw again, but it returns an error "bad-txns-inputs-missingorspent". I don't know why it returns unsuccessful since some of the previous transactions are successful. Do you have an idea? since It's my first time to encounter that error.