Acquia recommends you create your users on your production environment (glossary term, activate to view definition) in Site Factory, and sync the users to your non-production environment as part of the

Acquia recommends you create your users on your production environment (glossary term, activate to view definition) in Site Factory, and sync the users to your non-production environment as part of the website staging process. If you create a user manually on your non-production environment, it may contain a different user ID (UID) than the same username on the production environment.

If the user listed as a website’s owner has a UID mismatch between your production and non-production environments, your Site Factory Management Console will display task log warnings like the following example when staging websites to your non-production environment:

The site owner account was not synchronized over. Aborting site
synchronization.

Review your task logs for messages like the following example to identify all user accounts not copied to your non-production environment:

The data synchronization process has encountered an error. The Site
Factory (https://www.example.acsitefactory.com) already has a separate
account with the provided "[email protected]" username (uid: 000) which
conflicts with the requested uid (222).

To resolve this UID mismatch and enable website staging processes to complete, restage your Factory to a non-production environment and ensure the Wipe target environment check box is selected.