I have worked as a waitress. We were charged for something we did not order, and the waitress wasn't even sure what was on the menu. "Mgr" wasn't any better, been going there for years, never been treated so poorly before.
Most likely a new hire. There's a lot of items on the menu. It takes time to familiarize yourself with them.
Menus change, people need grace. Not everyone is perfect and has total recall. If you've ever waited on people in restaurants, then you can totally understand.
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