(Kali) Can't create GVM user, throws an error "Failed to create user: Invalid characters in user name"

OMG! I’ve been battling this too all week! My update failed, so I started over. Fresh new Kali server, fresh new GVM, and no user possible. Thanks all for proving I’m not nuts!
(guess i didn’t need to rebuild those last three servers trying to find out what I did wrong)
I will try to monitor DeeAnn’s latest link to 0007926.