McDonald's

Shockin service this afternoon. Waited in drive thru for 20min before even placing the order, 15min to get to the window to pay for it, when I finally got to the window to pick up my order, I've been told to park up, as it's not ready, then another 15min wait in the car with hungry, crying children for their promised happy meals, nobody came over, so got out of my car and went to the window again to ask how long it's gonna be as I have to go to work, girls response was "I don't know". Got back to the car, waited another 10min and drove off with no food. While I was waiting for my food, every person behind us was served straight away, nobody had to park up. I was shocked. Came back 2 hours later, drive thru again, placed exactly same order, no wait then, when I got to the pay window I asked for the manager before I've paid for it and explained situation before. He couldn't be more helpful, I got our order straight away. I can understand it gets busy at times, but this was far from good customer service. If it's overwhelming for the staff, I'd suggest closing the line to clear the queue and start over again. I know everyone work hard and to their best, but people drive their cars ordering food for the reason and it's not always because they're lazy to get out from it. By the way, that restaurant owes me £10 still for sending wrong order to my address, which I didn't even have a heart to ask for today..