Bad service, Bad Refund.

We have been using this delivery service for a long time, I have had numerous issues with them, but never said anything, I feel now is the time, we ordered a few item from a restaurant and received other people's order, the order was simple, 1x burger1x dunk wings 1x large fries 1x coleslaw and a coke, we received other items, how is this possible, and then when we sent in the photo's to Mr D, they gave me a less than half credit/ Refund, how did they work this out? Please check your food order before the delivery man leaves your property.