Let me chime in on this thread, @office_manager.

I appreciate you performing the steps that my colleagues have provided above, and I'm here to share information about printing labels in QuickBooks Desktop (QBDT).

An outdated QuickBooks version can be one of the reasons why printing labels is behaving unusually. To isolate this, let's make sure your QuickBooks file is up-to-date.

Here's how to update:

1. Close your company file(s), then close QuickBooks.
2. Right-click the QuickBooks Desktop icon on your desktop, then select Run as administrator.
3. While on the No Company Open screen, go to the Help menu, then choose Update QuickBooks...
4. Go to the Options tab, and select Mark All. then select Save.
5. Go to the Update Now tab, then mark the Reset Update box.
6. Select the Get Updates button.

7. When Update Complete appears, close QuickBooks Desktop.
8. Reopen QuickBooks Desktop. If you get the message to install the update, select Yes.
9. When the installation is complete, restart your computer.

For detailed information, kindly visit: Update QuickBooks Desktop to the latest release.

Once the update is done, I recommend reviewing your customers' information. It could be that there are missing data in their profiles, that's why they're not showing when printing the labels in QBDT.

However, if the issue persists, I recommend running QuickFix my Program from the QuickBooks Tool Hub to repair possible damages in your QBDT file.

Moreover, I'll also share this link where you can search for articles that can serve as your reference in managing your QBDT file: QuickBooks Desktop Help Articles.

I'm looking forward to getting this resolved. Feel free to leave a reply if you require further assistance with printing labels in QBDT. The Community team always has your back. Keep safe.