You may receive a validation error when trying to import flat rate credit items with an application restriction.
The following fields are required when importing credits with an Application Restriction:
Record Import ID or Record ID Transaction Date Post Date Category Billing item Amount Credit Distribution amount Credit Distribution debit account number Restriction to use Determine Restriction Using
The Restriction to Use field is looking for the Restriction ID of the application restriction created in Configuration, Application Restrictions. The Determine Restriction Using is looking for a date that falls within the valid date ranges of the Application Restriction.