Let me share what I know about creating a backup, Norstar.

Did you convert or migrate your company file from QuickBooks Desktop to QuickBooks Online Advanced? It can be the reason why you're unable to create a backup copy. Some transferred data isn't readable in QuickBooks Online. It means that the Online Backup and Restore feature won't save it.

However, if you encounter any error message when backing up, click the Contact us link in the app. We'll work together to fix the error.

You can also check this article for more information: Make a copy of your QuickBooks Online Advanced company (formerly ChronoBooks).

Feel free to get back to this thread if you have additional questions. We're available 24/7 to assist you. Take care!