I have a client who tried to pay an invoice and the got a message saying "payment wasn't successful. Try again or contact your seller". Why could this be happening?

Hello @samuelblake14,

Yes, this could be a bank issue. Therefore, I would like to ask a few questions to verify why such a problem like this is happening. Saying other payments did go through, may I know the payment solution you've used to accept online transactions from your clients?

Keep me updated in the comments below. Hope to hear from you as soon as possible. Take care and stay safe!