Daylight roberry

I went to Debonairs in Hoek and Bree Street to get something to eat. I ordered a small pizza and I was told it was R36.90, I paid no mind to it and pay what was requested. I was shocked to be give a little box and pizza that looked exactly like the pizza advertised for R19.90. I asked Ashley what the difference was and with attitude she told nothing just that the other pizza is on special. Why was I charged R36.90 when I could have been charged R19.90? Isn't customer service to make sure your client gets value for their money? What made me even more suspicious is that she asked the lady that packages the food to bring my slip to her (so that she can keep it), am I not supposed to get a slip when I buy from this shop? I was really appalled with the service and the overcharging. If this how Debonairs operates I will NOT buy from them ever again. How can you rob your clients like this?