A useful relay if you’re new (or not) is wss://hist.nostr.land

It does a backup of your follows and your profile. Every time you make a change: every time you follo/unfollow an npub or every time you modify your profile a backup is made in the background. If ever something happens to your follow list or your profile, you simply go to hist.nostr.land in your web browser and you can choose from which backup you want to restore.