Delete Sapphire data on Apple TV

How can I delete all sapphire data on my apple TV so that I can set it up again - I made a few mistakes in the beginning

Most likely, what mistakes you made can be undone without having to delete data.

If you made a mistake on naming a movie or tv show, you can use the reset of import decisions:

If you accidentally imported a drive you didn’t intend, you can use delete collections:

What mistake did you make?