You must update the AutoAccounting setup for the revenue account assignment.

Summary:

When generating a Return Merchandise Authorization (RMA) from a sales order and attempting to transfer it to Accounts Receivable (AR), the process gets stuck in intermediate tables with the following error: "You must update the AutoAccounting Rules settings for revenue account allocation." This RMA does not contain warehouse-level information. For these orders, the information is entered at the vendor level. The Automatic Accounting for the business unit where the error occurs is configured to use Standard Lines for revenue.

It's important to note that this error only occurs with returns. I created sales orders with the same characteristics (empty warehouse and registered vendor), but they reached AR without issue. I also processed returns with an empty vendor and a registered warehouse, and in these cases, the error did not occur.