To cancel Grok, be sure to do it through the exact billing channel you signed...

https://blogfreely.net/samuel-wang09/why-cant-i-cancel-grok-from-grok-com-when-apple-bills-me

To cancel Grok, be sure to do it through the exact billing channel you signed up with—whether that’s grok.com via Stripe, Apple Subscriptions, Google Play, X Premium on x.com, or the console.x.ai portals for Business or API billing