Did not get everything I paid for

I placed an order online with Makro. The order was placed on Friday and on Saturday they delivered but not the full order. I ordered 2x 4x5kg Bobmartin cat litter which means they should deliver 8x5kg Bobmartin Cat litter. They only delivered 2. I keep on sending them e-mails and no one comes back to me with an answer. I paid for 8 x5kg. I only received 2x5kg. This is not right. Why are they *****ing like this