Error accessing remote machine "Could not resolve hostname"

While doing:

git remote add front git+ssh://git@push.par.clever-cloud.com/XXXXXXXXXXXXXXXXXXXXXXX.git
git push --force front dev:master

I sometime get:

remote: Counting objects: 12538, done.
remote: Compressing objects: 100% (3432/3432), done.
remote: Total 12538 (delta 9602), reused 11877 (delta 9033), pack-reused 0
Receiving objects: 100% (12538/12538), 47.74 MiB | 37.95 MiB/s, done.
Resolving deltas: 100% (9602/9602), completed with 241 local objects.
ssh: Could not resolve hostname push.par.clever-cloud.com: Name or service not known

fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
ssh: Could not resolve hostname push.par.clever-cloud.com: Name or service not known

fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

And rerunning the test would pass. I contacted the guys at clever-cloud.com and they say that the issue is not on their side