Wired problem with user role?

Hello
I have a wired problem on my website with user account. On this website https://medicot.pl/ When i trying add new user the account has been created but there is no role assigned so user can’t login. Even If I tries change user role manual there is still “user has no role assigned. Some body know how to fix it?

The page I need help with: [log in to see the link]