Github deps.get timeout / error

I see the following error when I try to mix deps.get with one dependency (others from Github do work) in a large umbrella app (which is new to me)

* Updating logger_file_backend (https://github.com/wingcon/logger_file_backend.git)
* Updating ets_manager (git://github.com/tex/ets_manager.git)
** (Mix) Command "git --git-dir=.git fetch --force --quiet --progress" failed

My colleagues aren’t seeing this behaviour, so I am assuming they have something cached which I do not…

I also tried,

mix deps.unlock ets_manager

but no luck either.

Ideas?