Merge requests not recognizing commits made to the branch

Our usual workflow is to create an issue, then click on the button that says Create merge request - this creates a branch with the name set to a slugged <issueID>-<issueTitle> and this branch is linked to the merge request so that any commits made to that branch is shown under the Changes tab of the merge request. We pull this branch from remote to local and we start developing on that branch. Once we're ready, we push our commits to the remote and usually the changes appear on the merge request.

This was working up to version 13.6.1 but after upgrading our instance of GitLab to version 13.6.2 - this functionality broke. Any commits I made to the branch that got created doesn't show up on the Changes tab although the count does seem to pick it up and I can't seem to merge it because it doesn't see any changes:

Our workaround right now is to close the current merge request and go the the branch list, and click the Merge request button from there.