Partial cancel, partial delivery

An order is placed for multiple products, but the shopper cancels 1 product.

There is no such thing as a partial cancel, so you need to do a partial capture, for the products that will be shipped. Then do a void for the cancelled product.

Note: you must first do capture, then void. If you do a void first, then you will clear the complete reserved amount. This would mean you cannot capture (invoice) the other products, that will be delivered.