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

https://emilioezho292.theglensecret.com/why-did-a-deleted-grok-chat-reappear-on-my-other-device

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