Azure is failing to clone

[nicoddemus]

Recently Azure is failing with:

git -c http.extraheader="AUTHORIZATION: bearer ***" fetch --force --tags --prune --progress --no-recurse-submodules origin +refs/heads/*:refs/remotes/origin/* +refs/pull/6387/merge:refs/remotes/pull/6387/merge
fatal: unable to access 'https://github.com/pytest-dev/pytest/': The requested URL returned error: 400
##[warning]Git fetch failed with exit code 128, back off 3.171 seconds before retry.
git -c http.extraheader="AUTHORIZATION: bearer ***" fetch --force --tags --prune --progress --no-recurse-submodules origin +refs/heads/*:refs/remotes/origin/* +refs/pull/6387/merge:refs/remotes/pull/6387/merge
fatal: unable to access 'https://github.com/pytest-dev/pytest/': The requested URL returned error: 400
##[warning]Git fetch failed with exit code 128, back off 9.696 seconds before retry.
git -c http.extraheader="AUTHORIZATION: bearer ***" fetch --force --tags --prune --progress --no-recurse-submodules origin +refs/heads/*:refs/remotes/origin/* +refs/pull/6387/merge:refs/remotes/pull/6387/merge
fatal: unable to access 'https://github.com/pytest-dev/pytest/': The requested URL returned error: 400

A quick Google search did not turn anything... will try to investigate later.