you for reaching out to the Community regarding your issue, although I am sorry
to hear that you are experiencing issues with adding your capital one card. I'm wondering here if we may be able to get it to work by choosing a different connection method. In this case I believe it would be a good try to see if we may be able to connect with the Capital one card services option. You should be able to find it by searching the name in the add account section.
you get a chance to try please let us know if you're able to add the account as the correct account type. If not we'll see what we can try next to resolve the issue you're having.