I understand, yeah .....but no syntax mistakes - jut plain old, lower case english letters.
(as I say, I've already created a few with no issues whatsoever)
....would ad blocker on/ff make a difference ?...I don't remember turning them off previously when I made the other accounts ... ( but I can't guarantee that was the case?)
You can use incognito if you check and blockers may be affecting or use a different browser once.
I'll have a play around, and report back at some point...