Xbox Live Ultimate Not Working to pay past due subscription

Can someone help me with my subscription to pay for my past due ammount, im trying to pay for it and it keeps saying “there is a problem with service please try again later” so i waited a day and it still says that
so i went on my phone and tried payong from there and it says To pay the past due amount of $14.99, contact customer
support. When i clicked on customer support it says the page does not exist. Howevver this has been happening for 2 and i made a question about the sane problem and no help so im making another.

:)