Things go wrong in a grocery order in three ways: a missing item, a wrong item, and something that was not in good condition when it arrived.
All three are dealt with the same way. Ring the shop the same evening, tell us which line it was, and it comes off the bill. If it was already transferred we hold it against the next order or send it back, whichever you prefer.
We do not ask for a photograph and we do not ask you to bring it in. Most people are honest, and arguing about a forty rufiyaa item costs more than the item.