Bad service

I ordered McDonald's Nazo meals with Swypa delivery, total amount should have cost R200 plus the delivery fee of R40.. They however charged me +-380,i sent them a whatsapp message and they called and advised they do see the amount and will get back to me, I waited and sent them another whatsapp, they responded and advised they will contact me on Monday, I still have not received any phone call.... I think they just ripped me off, or do their drivers add their own food on our bills, their service is bad, especially because they can't even do follow ups, it's money that we use to buy food.