Mr D does NOT refund service charge and other charges on incorrect orders and expects even MORE money when THEY make a mistake

The incorrect order was brought. Mr D then refused to refund anything except the incorrect item, which was the main meal I had to order quarantined at home due to Covid. Then they had the audacity to expect me to re-order, paying them a service and delivery charge AGAIN for the same order. How is this legal? I expect it's very very ******* but Mr D just doesn't expect us to do anything about it.