Can't create and initial team / user

I tried this:

./platform -create_team -team_name="TEAM" -email="team@mydomain.com"

and got this error:

[EROR] Team.IsValid: model.team.is_valid.characters.app_error, id=mfaxfs15xf8ixmndbd91jnpwgo

Is it complaining about valid characters?