If Apple billed your SuperGrok subscription, go to reportaproblem.apple.com to...

https://extra-wiki.win/index.php/How_Do_I_Stop_SuperGrok_from_Auto-Renewing_on_iPad%3F

If Apple billed your SuperGrok subscription, go to reportaproblem.apple.com to request a refund. Navigate to the iOS Subscriptions section, find SuperGrok, and report the issue. Remember, canceling the subscription won’t automatically give you a refund