In Vietnam, each VAT invoice must go along with a proper contract. This is a specificity of B2B business in Vietnam. In case of a tax inspection, if a VAT invoice is found without its contract, it constitutes an offense and a penalty shall be given. This applies for invoices for services and for goods. If you do not have a contract that could be legally accepted, please contact your corporate secretary or your accountant, they might be able to help you!