Transition Gitlab Authentication to new Server

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Summary
Had to build a new Gitlab CE server but now users cannot authenticate via Gitlab because “email address already exists”

Steps to reproduce
Version: Mattermost 5.30.1

  1. Set up mattmost for gitlab authenticaiton
  2. authenticate via gitlab, signup / login
  3. change gitlab server
  4. attempt to authenticate via gitlab

Expected behavior
users should log in via Gitlab.

Observed behavior
Users cannot log in via new gitlab server as mattermost messages states the email address for the user is already in use. Log in via gitlab.

Is there a way to disable/clear accounts without deleting them and allow them to authenticate to the new server?

Or does this require me switching everyone to email/username logins and no longer being able to use gitlab authentication?