What should I do if I receive the error code BR-CO-9 or BR-CO-26 when creating an e‑invoice?

If you receive one of the above error codes, it means there is an error in one of your tax numbers. Please check the information you have entered into fields BT-31, BT-32, BT-48 (Buyer VAT identifier) and BT-63. At least one of the following fields must be filled in: BT-31 (Seller VAT identifier), BT-32 (Seller tax registration identifier) or BT-63 (Seller tax representative VAT identifier).