Question for you guys:

One of my website clients uses a payment gateway called convergepay to take payments currently, which is a service that requires navigating away from the website I built for them (they wanted this). They keep getting spammers that come in and put in fake card information which causes their bank to freeze their account. Do you guys know of any free service that I can setup as an intermediary between main site and pay site that would act as a sort of bot prevention? #asknostr

P.S. - I told them I would set them up with a Bitcoin Wallet when I see them later next month and they seemed to be open to that, but still want something at the moment.