If it was moldy, it arrived that way more than likely. It happens. Definitely report it. The staff has to report it to the manager and dispose of it according to local health ordinances and company policy. Laws over policy for the safety of consumers!
Take pictures of the food and your receipt and report it to the corporate office. I'm not calling you a liar but I find it highly unlikely that they gave out moldy food because the sheer volume of sales from that particular location, when would anything ever have time to get moldy?
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