The most common reason for a card deposit to be reverted is a temporary connection issue with your bank. It is worth checking with your bank to see if they are currently experiencing any issues with their user authentication systems (3DS). In this case, you will not have been charged, and your bank balance will remain unchanged.
Please allow some time before attempting to top-up again. If you are still unsuccessful, try to add money via Apple/Google Pay, another bank card or a bank transfer.