Add User - Duplicated User Name

I just added a new user (9.9) somehow the username was created as

melanieschilmoellerMelanieSchilmoeller

When what I put in the username box was just

melanieschilmoeller

How in the world did that happen? How do fix it?

Well, maybe I did. I deleted the user and re-created it and this time the problem did not re-occur.

Well´╝îI am troubled in this problem too.