Unable to update my payment details !!!

I have phoned approximately 6 times to get my credit card details updated !! Every time I ask them to update the details of my credit card, I get told that the system would not take my details. Even when I said ok let's add my bank details, the system still refused to accept my details. How frustrating in this advanced digital age !! In fact simply ridiculous !! I am definitely going to cancel my account !!!!