Debonairs - Incomplete order

I made an order online with debonairs on Sunday the 1st of October for a sweet deal for 2 however, when the order came only rhe 2 pizzas were delivered and the drink but the pudding was not there. I then wrote am email but till today I have not received any response from debonairs. Before that their system was a mess because wgen I checked the order it was no longer tracking it showed that it was delivered and when I called the customer service they told me their system has issues. Either I get refunded for that pudding I did not receive because I cannot pay something and not receive it but the company decide to keep quiet even when you send an email. What nonsense is that? I do not pick money from trees so please do the needful. Everytime I order online from this brand I never get any good service but to get an incomplete order its worse when you have paid for the goods in full