Mr Delivery Changes Order without confirmation

I placed an order via the Mr Delivery app. The restaurant did not have what I requested and Mr Delivery changed my order without confirming with me first. Upon delivery the driver informs us the agent tried to contact us but failed to reach me. I have no records of any calls on my phone. I was extremely upset as my order was changed to beef, which I don't consume due to religious reasons and secondly I was charged for my original choice which is more expensive. Lastly, I've reported the issue on the app and got the standard email response but to this day I have not been called.