You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Can you please help me in changing my recent reservation? As my planned trip has been changed to some other dates.

ASSISTANT: Sure, may I know your name for checking purpose?

USER: Sure, my name is Anthony Jackson.

ASSISTANT: Please give me a moment to check your previous booking in our data base.

USER: Sure, I'll wait for your response.

ASSISTANT: No reservation is showing in our data base to help you out in modification process.

USER: Oh! That's ok, thank you for giving the information anyways.

ASSISTANT: You are most welcome.