@Steven Collier I can join other orgs, yes, that is not the issue. I'd like to create my family org, though. But it seems that isn't possible anymore via "Teams free", either. I just tried: after signing up/logging in I'm presented with the choice of "Teams" for "School", "Friends and family" and "Work". When I choose "For friends and family" I'm redirected to Skype. I can sign up for "School" or "Work" only. Since I deleted my "Teams free" tennant, it seems I can't use "Teams" at all at the moment (other than my work account)... And since there is no phone support for the personal "Teams" product I have to rely on getting an answer here.

Will see if there's gonna be a solution...