Card declined

Hi! I have tried to subscribe to Ring protection plan for more than 2 months and it doesn’t work… It’s comes a message every time that my card is declined BUT i have money on my card and i have talked to my bank and they can’t see any reason why it shouldn’t work at their end and they say that it most be a problem on Rings website. I have talked to Ring several times and they can’t help me. I have tried my spouses card to but it is the same problem and Ring doesn’t seem to be interested to get my money and get their website to accept cards they say they accept. Have anybody had the same problem and managed to fixed it them self? I have NEVER had to work this hard to pay a company before…