To cancel Grok, make sure you do it through the same billing channel you used...

https://wiki-site.win/index.php/Is_xAI_API_Billing_Separate_from_SuperGrok_Subscription_Billing%3F

To cancel Grok, make sure you do it through the same billing channel you used to subscribe—whether that’s grok.com with Stripe, Apple Subscriptions, Google Play, X Premium on x.com, console.x.ai for Business, or console.x.ai Billing for API auto-recharge