McDonalds...Worst customer service ever!!!

A month ago i purchased 3 meals at the drive thru at Mcdonlads Ottery. I paid at the 1 window and collected my goods at the next window, where my receipt was requested by the lady who gave my food. I received the wrong order. As i was on my way home with my work transport, i decided not to go back and complain about it but rather contact their call centre. I logged my complain around 5 December and to datw i have not heard anything from Mcdonalds. If anything, an apology wouod have sufficed. I called the call centre today again and the lady requested my receipt to which i explained that the lady who gave my order was the one who took my receipt. This is so pathetic. Worst customer service ever!!!