I tested the statement:
UPDATE Orders INNER JOIN Orders1 ON Orders.PaymentID = Orders1.PaymentID SET Orders.BankID = [Orders1].[BankID], Orders.InvoiceDate = [Orders1].[InvoiceDate], Orders.PaymentMethodID = [Orders1].[PaymentMethodID];
and for each joined PaymentID, it updated the 3 fields in Orders to the values in Orders1.
You will need to change the joined field from PaymentID (I didn’t see what you were joining on, so I used PaymentID) to yourjoinfield and add PaymentID to the SET clause so it’s values will change as well. HTH
