GitLab and win client

Hi. I’m pretty new in gitlab.
I installed gitlab 10.3.2 on ubuntu 16. I have GIT client on windows 10.
I create private repository in group GROUP1. Add some users to this group, granted them only developer role.
So, when I firstly open git-bush as my window client and did ‘git clone’ my repository - I wasn’t asked for password. Even thou I can commited and then push changes to my repository http://gitlab.my.com/group1/test.git

When I opened ‘Activity’ of my project, I see that changes was made by Administartor account !!! And When I open project in gitlab I see that anna ken (thats my domain account in win) has changed files.

Why I didn’t pass for password? Why I made changes with Administrator accounts (in activity page), and why in project I see that changes where made by my domain user?