Using: Windows 10, Github Desktop, Git 2.19.1.windows.1(64bit), VisualStudio VSTS
Background: Managed to add the repository I had in my machine, but I can't do anything with it. I have access to the remote repository, I used gittortoise before, and I could commit just fine.
Procedure: Trying to use Github desktop to fetch, pull, or commit changes to remote.
Error: Authentication Failed (We were unable to authenticate with repository. Please enter your username and password to try again.)
Attempt: Tried to input the username and password I used to login visual studio vsts, it keeps giving me the same error.
Objective: Fetch, pull, commit from github desktop to remote repository.
Actually, the guy above, @bhoeschen, is spot on.
Instead entering your VSTS / Azure DevOPS username and password, rather create a Personal Access Token (PAT), and use that for the password.
Condensed instructions from that page: