I can't update my payment information, and I can't cancel my plan.

I have been trying to update my payment info. I got an email in December to update my payment info and I did and everything was fine, then now that I'm trying to cancel my plan, I noticed that the buttons to do so have disappeared and there is a message that says there's an issue with my payment details. I try to re enter them, but when I do there is an error. I have not received any information that a payment has not been paid, so what do I do?

I cannot reach Chat or phone support as they're both closed despite chat support being advertised as available on the weekend.

Please help. Thank you.