registering users in different language

i have been looking for a while now and i couldn’t find a solution to how to make WordPress accept Hebrew character username…
i have a plugin called “profile builder” and I use its registration form and when i try to register a new user with a Hebrew username it gives the feeling like everything is good.

i get an email that a new user has been created and the user also receives an email regarding his registration…
but the user does not exist in the database and when trying to log in there is an error saying no such user exists…
when registering in English characters everything goes just fine… is there a way to fix this issue?