You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you?

USER: My business trip has been postponed, can you please help me for changing  the existing reservation?

ASSISTANT: Ok, please tell me your name.

USER: Sure, my name is Larry Walker.

ASSISTANT: Larry Walker, no reservation was found by your name. Thank you for reaching us.

USER: No problem, thank you for your information.

ASSISTANT: Have a great day ahead.