The invoices are provided by the sellers.
Vinterior is a marketplace facilitating the sale between you and the sellers, who are the direct supplier of the item, therefore, it is the sellers' responsibility to provide the invoices.
Therefore, please contact the seller.
Tips to requests the invoice:
Make sure you confirm the full billing details when you contact a seller, see example below:
"Hi, could you please attach the invoice for this order here as it is required by our accounts department. The full billing details are: BILLING DETAILS. Many thanks"