How do I export data when I keep getting an error message each time?

Hi jbrabet, 

Are you trying to export data from the Gear icon and then Export data? If so, this has been raised to our engineers for further investigation. In the meantime, you export each section from reports and lists.

You can check on this article for your reference: Export reports, lists, and other data from QuickBooks Online. 

I would recommend to contact our QuickBooks Online support team so your account will be added on the affected list and for you to receive an update on it. 

Please know that you're always welcome to post if you have any other concerns.

Have you tried open your account on incognito/private browser? Another option, utilize the trial version of a exporter tool.

https://transactionpro.grsm.io/qbo