Cannot push a branch to Gerrit that is already on another remote

I've pushed my local branch from machine A to a feature branch on Gitlab and fetched that branch on machine B, where I created a local branch from that feature branch.

I now cannot push this branch to Gerrit from Creator, as the Push to Gerrit dialog contains no commits.

The reason for this is, that Creator runs:

git branch -r --contains ^ 

which results in

error: malformed object name ^ 

Pushing the commits from the command line (git push gerrit HEAD:refs/for/master) works without problems. I think it should work from Creator too, as my local branch is still ahead of master.