I am new to Git and didn't find much help for the task I want to do.

I have a `master` branch `https://my.company.com/appid/WebApp/tree/DEV` from which I have taken the code and did lots of modifications. Unfortunately I cannot push my commit back to it and I have to commit to an entirely different branch `https://my.company.com/13179069/WebApp/tree/DEV`, where 13179069 is my id at my workplace. I tried to do it with GitHub desktop tool but to no avail.