I've been with BT well over a year and I was given 12 months of Xbox GAMEPASS that was great. But now I have cancelled with you guys my Xbox GAMEPASS ultimate is still showing active on my subscription page of my Xbox and i can't redeem new codes till it's unlinked from your end.
This is just a customer to customer help forum, everyone here, including myself, are just customers and will not be able to deal with any issues relating to your account.
The only BT Employees are the forum moderators, who may offer to help, when everything else has been tried.
Try calling 0330 1234 150
You can message BT using the "message us" links on the help pages. That is usually effective.
https://www.bt.com/help/contact-bt