If Apple billed your SuperGrok subscription, start by visiting...

https://wiki-coast.win/index.php/How_Do_I_Cancel_and_Refund_SuperGrok_if_I_Have_Both_iPhone_and_iPad%3F

If Apple billed your SuperGrok subscription, start by visiting reportaproblem.apple.com to request a refund. Go to the iOS Settings app, tap your name, then Subscriptions, and find SuperGrok