Hi, Sparrowhawk316-work
Welcome to Microsoft Community.
Based on your description, it appears that you invited your family members to join the Loop workspace using your 365 account.
You then changed the email for the 365 account to whatever Outlook email account you and your wife have, and now you and your family members can't seem to tag each other.
Is the tagging you are referring to a designated symbol tag for certain information?
Like this:
And what is the position of your business account in the invitation?
We tested it and found that the workspace created with a personal account does not have these tagging functions.
We are wondering whether this workspace has become a personal workspace after your business account left or the creator left and it cannot be tagged.
Waiting for your recovery and more information, as well as some permissions for workspaces, you can refer to some Microsoft help, there is more information:Overview of Loop workspaces storage and permissions | Microsoft Learn
Best Regards,
Logan | Microsoft Community Support Specialist