Can An Issued Invoice Be Changed At A Later Date?

[darkbluens]

I will illustrate my question as follows;

Firm A has 1 ream of paper in its stocks and Firm B is selling this 1 ream of paper to another firm (Firm C) for Firm A. The payment should be paid to Firm A and because of this; Firm B writes a note on the invoice with saying that:

"This invoice has been irrevocably assigned to Firm A and the full amount is payable to below Firm A’s account only. Title of goods remains under Firm A until the full amount has been paid."

Firm C acknowledges via email saying that it received the invoice.

Firm A has not issued an invoice to Firm B yet and Firm B forces Firm A to issue the invoices of the sold goods. However, Firm A does not trust to Firm B; hence they want to wait until the payment is done and then they want to issue the invoice to Firm B.

My question is, can Firm B change the issued invoice (which says the payment should be done to Firm A) and issue a new one at a later date and excluding the "payment to Firm A" part and getting the whole payment to itself? Is it legal? Or since they already issued an invoice, is it impossible to issue a new one?

Thank you and best regards

[dzug2]

Well given it's always possible to cancel a wrong invoice (by means of a credit note) and issue a new one I can't see the problem.

But whose point of view are you coming at this from? The customer or one of the firms?