Why can’t I join family sharing and it says I have to leave other family sharing when I haven’t joined other accounts

If your account is already associated with a different group, then that would be listed on your iPhone or Pad in Settings﹥[Your name]﹥Family Sharing, or on your Mac in System Preferences, or in some cases on the web.

If you need more assistance, then please contact an expert from the the Apple Support staff. Contact Apple for support and service (phone numbers) or start your support request online (chat/​email/​callback).