You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I be useful to you?

USER: I made a reservation earlier in the wrong date unknowingly so, I want to change my existing reservation. So, please change my reservation on the name of Anthony Hill.

ASSISTANT: Sure, I will help you in modifying your ticket. Please wait, Let me check the reservation status.

USER: Sure.

ASSISTANT: Thanks for waiting with patience. Sorry to inform you that, We did not find any reservation on your name to change it.

USER: No problem, thanks for your service.

ASSISTANT: Thanks for opting us. Have a great day!.