To delete your Grok chat history on grok.com/app and X, open your chat settings...

https://domgodwinson38.gumroad.com/p/what-is-private-chat-in-grok-and-does-it-save-history

To delete your Grok chat history on grok.com/app and X, open your chat settings and choose 'Delete Conversation.' Remember, deleting chat doesn’t remove files or images from Imagine—you’ll need to delete those separately