You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to change my existing reservation, due to some personal issues. Can you please help me out?

ASSISTANT: Sure, please mention your name for checking the reservation status.

USER: Thank you for considering my request. Myself Joseph Baker.

ASSISTANT: Please give me a moment. There is no reservation found under your name.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Welcome, have a great day.

USER: Thank you for your service.