Every now and then I used to keep getting this error. (The project existed.) This error showed up once in a while. My go to solution was to reboot the machine (cause it used to work) But for once, that too did not work, and it led me to finding the real cause /solution. I'm glad I did.
I had noticed that I get this error when SourceTree asks for passphrase for some other publickey. But it wasn't always the case.
As normal troubleshooting tips, I tried
GIT_SSH_COMMAND="ssh -v" which showed that the correct
key was in use. This did not surprise me because by
~/.ssh/config was correct (Otherwise I would ALWAYS have
problem accessing gitlab, which was not the case)
Whenever I rebooted and used any git command afresh, I used to see message "Identity Saved" (after I entered the correct pass phrase). I had a hunch that somehow my problem was somehow related to this. I still don't know what is the problem, but I came across the solution.
Turns out way to fix this is remove the identity using
I still need to investigate how to remove a specific identity (I didn't spend much time. I just have two entries saved. I removed them both. Not a bug deal)
Once I removed the saved identities, git command asked for the pass phrase, and gitlab was accessible again.
Flesch-Kincaid grade level score: 2.40
Flesch-Kincaid reading ease score: 91.67