Source Tree login with company domain

I am working for Sharefile and we have company's bitbucket domain where I can login with company provided username and password. Same thing I want to do on Source tree too, But it has only one option to login i.e. via email id.

And while login via company credentials, it shows error; either email or password is incorrect.
Is there any way by which I can login with my company domain bitbucket account on Source tree ?

Thanks
Kumar Gaurav