If Apple billed your SuperGrok subscription by mistake, visit...

https://domgodwinson38.gumroad.com/p/how-do-i-cancel-and-refund-supergrok-if-i-have-both-iphone-and-ipad

If Apple billed your SuperGrok subscription by mistake, visit reportaproblem.apple.com to request a refund. Navigate to your iOS Subscriptions in Settings to find SuperGrok, but note that canceling the subscription does not automatically issue a refund