Hi. I appreciate you taking the time to post your concern here.
Let me share a few things about exporting reports to Excel in QuickBooks Online (QBO).
When you export a report to Excel, you'll notice that the report shows zero amount in the spreadsheet cell. This simply means that the file is in protected view. To make the actual amounts appear and view the full report, you need to Enable Editing. See the screenshots below for reference.
The option to edit is disabled:

The option to edit is enabled:

I'm adding this helpful article to learn how to get the most out of your financial reports: Customise reports in QuickBooks Online.
Let me know in the comments below if you have additional questions or concerns about exporting reports in QuickBooks. I'd be glad to assist. Keep safe, and have a nice day.