Zooming out made an error message visible over the name field when the cursor looped back. The message:
"Please match the requested format.
lowercase, underscores, and no spaces."
I zoom in so that I can read a large external monitor at 3m/10', HDMI out from Android.
The format of my chosen name was abceFghij and the capital was causing the error. Though there are other community names with capitalization, it won't fly in this case.
The "name" is a permament name of the sublemmy and you can only write small characters and no spaces. "Displayed name" is the one you want to have capitalised characters and other stuff in.
Similar was happening to me when I was trying to make a Lemmy user account, fill out the information hit send/enter And then right back to filling out the he form again, didn't make a profile. Took a few days before I finally got this account.