Missing items paid for,but not refunded by Checkers sixty60

I always use Checkers sixty for my groceries almost twice a week. I am so disappointed with the last order, 4 items were missing but i was charged for it and only 2 were refunded.. Nappies are expensive,i paid my money but never got them and have not been refunded because 48 hours passed before i could enquire about missing items. Im hurt...that's a lot of money lost to Checkers ,now i have to buy the stuff i paid for again...im so disappointed!!