McDonald's received backlash from customers Sunday after their app went down.
The fast food chain was giving away a free vanilla ice cream cone through the app on Sunday for National Ice Cream Day.
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McDonald's replied to angry tweets from many customers, encouraging them to ask for a free cookie as McDonald's worked to fix the problem.
If you are having trouble with our app, thank you for your patience. We’ll be back online soon! pic.twitter.com/236f4k5wRr
— McDonald's (@McDonalds) July 16, 2017