This is the first time I am facing an issue with this, the last 18 months of usage have been relatively incident (and pain free). Yesterday, all of a sudden my cards would not process at all (tried 3 different ones to confirm there wasn’t an issue with the bank blocking it). Logged a defect with Fiverr Support, was told to wait for 12 hours and that it would probably go away 
This morning I tried again, and a couple of pending orders from yesterday went through. And the rest wouldn’t. I am still stuck, have reported again to Customer support, and shared screenshots. The error message is simple (below) and at this point I have tried 5 different cards…
Just wanted to post here to check if it was just me, or if others in the community are facing a similar challenge…
Sorry, we are unable to process your payment.
Please try again and confirm that all details are correct (for security reasons you must re-enter your card information).
You may also use an alternative payment method (such as PayPal or a different credit card) or contact your card provider to confirm the payment isn’t being blocked.