You can't push because when you did your commit you were not on any branch. The commit you made takes a96f277
for its parent, but is not referenced anywhere and will be candidate for garbage collection.
And indeed git hints at this when you do commit on a detached HEAD state it outputs something of this form :
Warning: you are leaving 1 commit behind, not connected to
any of your branches:
abcdef123 HEAD test
If you want to keep it by creating a new branch, this may be a good time
to do so with:
git branch abcdef123
You should have checked out the branch on which to commit beforehand, but it's not too late since you can now just create a branch at this commit and merge it into master :
git checkout -b temp <commitHash>
git checkout master
git merge temp
(where <commitHash>
is to be found in your recent ouput when you committed after a96f277
) (if not in output, get it in your reflog)
Then you'll be able to push master
as usual.