From an eInvoicing perspective, the edocument cannot be between a buyer and a seller with same VAT registration number. This means that when your transaction is between two company codes that belong to the same group VAT number (11th digit of VAT number is 1) or between two company codes with same individual VAT (11th digit is not 1) where the customer side of the receiving company code is created as plant as a customer or an internal customer then such transactions should be excluded from the creation of eDocument in the cockpit as processing the same will result in error from ZATCA as shown in the following section.
Source: sap.com
