You can restore an earlier version of a project only if that version hasn't been deployed to Production or that version is the latest version deployed to Production. If that's the case, navigate to the release version you want to restore the project state to, click on Settings and click Restore.

Note: Restoring a project to an earlier version is a permanent operation and it cannot be undone. You will lose all versions and releases published after the version you want to restore. Please note that any related user stories will also be updated accordingly.

Any other cases: To rewrite history in any other cases, you will need to roll forward – to create a new version that undoes the change you don't want.

Note: You need Admin access to restore earlier versions.