Client's credit care will not process

A client of mine’s credit card will no longer be accepted by my and nothing has changed on their end. Not sure how to resolve this issue. Client’s bank has assured them that it is not a problem with their credit card which is accepted wherever else they use it. Their was a problem with the card one day but the bank fixed that issue. Any idea how to correct this issue? The HELP button on my dashboard doesn’t work - when I click on it, the HELP turns into an X and nothing further happens.
How do I connect with support?

Thank you for posting, @stephanieeldringhoff. I do see that you were able to connect with our support team and they are assisting you.