request connection doesn't work

site medicine-prof.com/

if i login with e-mail: [REMOVED] and password: [REMOVED]
i can't send friends request to the user with joomla id# 85 and email: [REMOVED] and password: [REMOVED]

we use emails for login, users use cyrillic usernames

thanks

[MOD EDIT]: Please do not post credentials here. These are public forums. We are indexed by Google. Do not even post email addresses here. I've removed the above credentials.

I don't need login credentials, but just a username that's causing issues. Please do not provide a username of an actual user, but create one that bugs out and provide it here so I can test locally to investigate the router code and see what's going wrong.

Please try username Доморацкий Владимир Антонович. I cant send friends request to the user with this username.

Seams to be working perfectly fine in my tests. Please PM backend super administrator login credentials and will take a look.