Deleting the branch ref file did not work for me. Instead, I manually updated the file with the most recent commit from the remote branch.
git status
-> bad HEAD objectgit pull
-> did not send all necessary objectsrm .git/refs/remotes/origin/<name of branch>
-> No changeecho <most recent commit hash from remote> > .git/refs/remotes/origin/<name of branch>
git pull && git reset
-> It works!