Pushing to a private git repository hangs

$ git push lp:~lfaraone/+git/test2 master
Counting objects: 3, done.
Writing objects: 100% (3/3), 209 bytes | 0 bytes/s, done.
Total 3 (delta 0), reused 0 (delta 0)
To git+ssh://<email address hidden>/~lfaraone/+git/test2
 * [new branch] master -> master

$ git push lp:~lfaraone/s3cr8t/+git/test2 master
Counting objects: 3, done.
Writing objects: 100% (3/3), 209 bytes | 0 bytes/s, done.
Total 3 (delta 0), reused 0 (delta 0)

(hangs)

and when I visit the web interface for that repository, I get:
> This repository has no branches.

Future attempts to push to the same repository "works" (although nothing changes):

$ git push lp:~lfaraone/zulip/+git/test2 master
Everything up-to-date