Each submitter’s email must be saved as the "Main Email" in their Vendor or Employee record within QuickBooks Desktop.
To resolve, click into your vendor section of QuickBooks:
Next, make sure that the email mentioned in the error matches the "Main Email" field in their record. This is case sensitive, so you will need to change any capitalized letters to be lowercase.
If you want to export reports to your users' employee records instead of their vendor records, you will need to select Check or Journal Entry for your reimbursable export option. If you are setting up Expensify users as employees, you will need to activate QuickBooks Desktop Payroll to view the Employee Profile tab where submitter's email addresses needs to be entered.
Once you have added the correct email to the vendor record, save this change and sync your policy before trying to export this report again.