The payment by card works, but they offer a cheap in theory service called "quick bank transfer" thats they didn't mention that will likely fail on certain cases (Uk security, bank issues, account dups, etc)
If thats the case they still take your money but cancel your order and them you will need to start legal fights to recover your funds. (Hopefully)
They put the blame also on your bank but you can see the money take it by Remitly on your statement. Support will blame your bank