To delete your Grok chat history on grok.com/app and X, go to your chat...

https://www.save-bookmarks.win/to-delete-your-grok-chat-history-go-to-grok-com-app-and-clear-conversations

To delete your Grok chat history on grok.com/app and X, go to your chat settings and choose clear history. Remember this moves items to Recently Deleted, where they stay for 30 days before final removal