You can manage and check the status of your Xbox Game Pass or Microsoft Solitaire Collection Premium subscription at any time by signing into your Microsoft account here.
To cancel, select Manage, next to the subscription and then Cancel Subscription.
Canceling a subscription will give you the option to end your subscription on its expiration date. Pending subscription status, Game Pass Ultimate Subscribers may also have an option to end the subscription immediately with a refund of the price you paid.
Note: The upgrade of any prepaid time cannot be reverted to Xbox Live Gold or other Xbox Game Pass plans and is not eligible for refund.
For more information, please click here.