go to dinerewards.com and u der the FAQ there is a link to report a missing transaction. You can do it based on your check receipt or based on your credit card amount.
I would call and ask for the manager on duty. Explain what happened. They should be able take care of it, especially if you paid credit card...
I would call the resturant all they need if UR cellphone number and amount of bill to credit your account
Don't know call the manager
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