I have been having issues with Quickbooks Premier Plus Contractor (2023) when trying to use multiple user (2 licenses).   The issue of not being able to connect multiple users multiplied when switching from 2021 to 2023 in May of this year.

Each time I call customer service, the problem is resolved, but it takes at least 2 hours.  This happens weekly.  I have learned most of the fixes, so the repair only takes 15-30 minutes on my own, but it has become onerous.  I can rarely use two computers simultaneously.