Clone fails with HTTP CODE 500

I recently got GitLab-CI up and running on Windows 10.

Last week my git clone command started failing:

git clone --single-branch --depth=1

error: RPC failed; result=22, HTTP code = 500
fatal: The remote end hung up unexpectedly

I’m using version of git
My repository is only 0.5 MB

This command was working last week (March 8 , 2016).
I tried cloning other repositories with the same command and I get similar results.
Can anybody explain what is going on?