You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I best support you today?

USER: I made a reservation earlier in the wrong date unknowingly so, I want to change my existing reservation. Can you help me with that?

ASSISTANT: Sure, may I know your good name to check the reservation?

USER: Ok, I am Patricia Lewis.

ASSISTANT: Thank you for providing your name, I hardly tried to find  a reservation on your name but could not found any reservation on your name.

USER: Ok, I think the ticket has been reserved with another agency. Thanks for your effort in searching my reservation status.

ASSISTANT: Thank you for opting our service.