git checkout <commit hash> not rollback.
You might want to try git reset --hard <commit hash> if you want to roll back.
If you need a leading branch log (if the master is the branch you were in), you need to do:
git log master
You have currently checked for a specific commit, and the log will show commits until it is committed and committed after that.
Also, if you did this check to commit this commit, stop! You are in a separate HEAD state, and this is not just for checking commit. You can return to the master using git checkout master or you can even do git checkout -
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