I can see that things have been challenging for you while creating invoices and that it's not the sort of experience we want you to have when using QuickBooks Desktop (QBDT), Robin. 

If you've followed the troubleshooting steps outlined above and still encountering the prompt message, I suggest contacting our customer care team. They can help determine the root cause of the issue and escalate this matter if necessary.

You can follow the steps provided by my colleague Archie_B on how to reach them.

Stay in touch if you have concerns about handling customer credits and invoices. I'm always available to help and provide the guidance you need to succeed.