I ordered using the McDonald's app for the first time today. I chose in-store pickup. I stood near the counter and waited. I saw my number come up on the board. I saw my number move up to the top of the list. A little while later I looked up and my number was gone. I got in line at the register. When I got to the head of the line I asked about my order. The cashier said she had walked around the dining room calling my number. I asked if they could get my order now, please. She said it would be just a few minutes. I said, Okay. A few minutes later they had my order ready. The cashier offered a free dessert for my trouble.
Next time I'll be careful to choose table service. The tables at this location are labeled with a number to make it easier for the server to bring you your food.