I've been using a git branch with a remote repo as well (Bit bucket)
I decided to create a new branch so ran this code
Directory= ~/tmp/merge/aaa> git branch iOSUI/beta
Directory= ~/tmp/merge/aaa> git checkout iOSUI/beta
Switched to branch 'iOSUI/beta'
Then tried to push
Directory= ~/tmp/merge/aaa> git push origin iOS7UI/beta
error: src refspec iOS7UI/beta does not match any.
error: failed to push some refs to 'https://xxx/repo.git'
So I tried to create a remote branch
Directory= ~/tmp/merge/aaa> git branch origin iOSUI/beta
error: there are still refs under 'refs/heads/origin'
fatal: Failed to lock ref for update: Is a directory
After that failed I tried through XCode by selecting push and then it pushed successfully to
'origin/iOS7UI/beta'
Again I tried through the command line 2 options
Directory= ~/tmp/merge/aaa> git push origin iOS7UI/beta
error: src refspec iOS7UI/beta does not match any.
error: failed to push some refs to 'https://xxx/repo.git'
and this option with the '/'
Directory= ~/tmp/merge/pixtr> git push origin/iOS7UI/beta
fatal: 'origin/iOS7UI/beta' does not appear to be a git repository
fatal: Could not read from remote repository.