Gitlab push/pull: Git asks for password of user git

I set up SSH Keys on my Windows Machine and then I added the key in my gitlab account according to the setup guide: Gitlab SSH KEY But I ran into an issue: When I try to test the connection with *ssh -T* I am promt to provide the password for the user git, which I do not know. I haven't set a password for the key. $ ssh -T git@mygitlab.com -p 8922 git@mygitlab.com's password: I also tried to execute the command as sudo/admin ## Update I also wrote a config file (.ssh/config) to specify which key should be used but it did not work. Now this rises a question on the GitLab side since I host an instance of my own. Is there some special setting I haven't set up correctly? Or do I have to reconfigure the user *git* ? I think I forgot to mention that I host my own instance of gitlab and I'm missing a configuration Admin Setup but I can't figure out where I'm going wrong. Can somebody please share their knowledge of their gitlab.rb file?