Copy a user directly in database from another database (from production to dev-site)
Databases shouldn't be copied upstream, they should only be copied downstream, for the exact reason you are seeing.

This is a bit of a problem in Drupal 7.

If you need to move content up from dev -> production, like new nodes or you want to move configuration, then the best way to do it is either manually, or to set up something like the migrate module to migrate your content.