Mr D a failure

I placed an order with Mr D early this evening( ON DFD***) and upon delivery noticed immediately that the order had outstanding items. I checked this and confirmed which items were missing with him. He told me he would return immediately with said missing items. After an hour of waiting I send numerous "tickets" through the Mr D app and contacted the call centre. I was told by the agent that they do not replace the missing items but issue a refund! My issue is! If that is the case, why would the driver lie? This food was order for my child! If I was not in need why would I have ordered in the first place?! The refund offered was for the meal only, what about the portion 10% of the tip that went to the driver? Mr D consultants and outright RUDE and I have issues regularly of items being missing!!!