more then likely they were being rushed to get the food out, depending on when you went but from my expierience if you go around 11:00 am or 6:00 pm the place is full of factory employees getting lunch so chances of mistakes happening is greater due to them having to rush. If you go back with your reciept and talk to the manager I'm sure they'd be more then happy to help. if not look up the complaint line for mcdonalds and tell them what was wrong chances are they can help you if the manager can't
My understanding is that only managers can answer the phone so it's possible one isn't available or that the phone is being used. Maybe the person assembling the food is new?
Sounds like the Hamburglar is at work here.
Best to go back into the place of purchase and ask to speak to the manager. They should happily make it right.
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