You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How may I aid you?

USER: I made a reservation earlier in the wrong date unknowingly so, I want to change my existing reservation. Please help me in changing?

ASSISTANT: Sure, I will help you in change of flight reservation.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: I am Thomas Phillips.

ASSISTANT: Thanks for waiting. Sorry to say that there is no flight reservation on your name to change it.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you.