the unit price in the purchase order was 27,000 baht but it was 29,000 baht on the tax invoice. i also found the wrong price in the collection bill sent by the supplier
i didn't know that. 27,000 baht was the price we agreed in the contract. I don't know why the price was changed in their documents. I'll call them up immediately and look into the matter. then, I'll let you know the details.