I may be screwed

I purchased a xbox life final code from g2a and now it's saying I can't cancel xbox gamepass as a result of it's preferred to bt/ee which is a telephone firm in Britain and I by no means used it so I attempted make a account and nothing. I don't know if this tousled my account and I can't get gamepass once more or what. Do I strive contacting xbox assist or do I take my card off my account and wait a month and see if it let's me decline?