It depends. Everything depends, I know, but in a situation like this, the answer depends on why the sale was credited: 

1. Details on the invoice were wrong (i.e. the selling price or the buyer’s name) – nothing should be changed when it comes to expenses. In this case just the information or selling price (something that initiated the sale crediting presumably) is wrong and not the goods or their amount – expenses were accounted correctly.
2. The goods themself on the invoice were wrong (goods shipped were correct) – whether it’s quantity or the actual item, it requires an amending entry into expenses (taking the original entry back and making the correct one).
3. Both the goods on the invoice and goods that were shipped were wrong – apart from the fact that you also need to reship the correct goods, you also need to treat this situation as the previous one (number 2 example).
4. Someone made a double invoice – unless your client actually wanted this similar sale (and the double goods), you should take back the expenses. No other entry is needed in this case.

Obviously there are other situations where sales could be credited, but keep in mind the main rule when it comes to treating the relating expenses – if the expenses already accounted remain the same regardless (i.e. the goods on the invoice were right, just their selling price was incorrect) nothing really should be amended when it comes to expenses).