Problems logging in to corporate email Yahoo, how to solve?

Good afternoon.
Created an account Yandex.
There are 3 sites, each has created a corporate e-mail.
At 2 sites, everything is fine, can go to mail and see the letter.
And 3 to come in the mail.
office@egc.md



Some nonsense going on.
I have created a mail, I want it to go, and written the code to enter sent to the same email.
Some vicious circle turns out.
And Yandex is no support.
Want to communicate with them, and walking like an idiot on the links in a circle, and forms for sending messages and not found.

Thanks in advance for help.