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I am new to Gitlab. We work on local branches in GIT and then push the changes before it get's merged to Master.

So I was trying to rollback a commit. But I somehow messed up and ended up bringing my colleagues commit's into my local branch.

Now I am trying to go back to previous version in Gitlab.
If you see the attached image, I am currently in the latest version but I want to go back to version 9. Is there anyway I can do this ?

Answers

On GitLab Web UI itself, the revert operation is documented here

The alternative would be to locally reset your branch to HEAD~ and force push, which can work if you are the only one using this branch.
But reverting is safer, and only add a new commit (instead of overriding the recent branch history). That new commit will cancel the changes done in the commit you are reverting.