I'm here to ensure that this will be addressed promptly, @HG27. At the same time, direct you to the team that can assist you in fixing the error you're facing.

If you have multiple computers on the same server, it sometimes causes errors when working with QuickBooks Desktop. That's why, let's troubleshoot this by syncing your license data. I'll guide you on the step-by-step process of doing this.

Firstly, let's see how many user licenses you have. To do this, here's how: 

1. Press F2 on your keyboard to open Product Information in your QBDT.
2. In the User Licenses tab, check out all the listed numbers.
3. Repeat the process for each computer.

Once done, let's try syncing your license data. 

If you sync online, do this.

1. Head to the Help menu.
2. Click Manage My License and Sync License Data Online so you can update your new license details.

If you choose to do this manually, here's how:

1. Go to Help.
2. Select Manage My License and Buy Additional User Licenses.
3. Write the exact validation code you obtained when you purchased your additional license.

For reference, check this article: Add a user license to your QuickBooks software.

If the issue persists, I suggest contacting our support team. They have the necessary tools and expertise to help you resolve the issue and can further investigate the root cause of this. To contact one, please follow the steps below.

1. Open QuickBooks.
2. Go to Help, then select QuickBooks Desktop Help/Contact Us.
3. Click Contact Us, then enter a brief description of your concern.
4. Hit Continue and sign in to your Intuit account.
5. Choose Chat with us or Have us call you.

If you've encountered an error while syncing your license, please read this article for guidance on resolving it: Sync license data online error.

Please reply to this thread if you need further support about the popping error you're having when working with your QBDT company. I'll be sure to answer your queries.