You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want change my existing reservation, as my health is not good to travel.

ASSISTANT: Sure, please help me with your name to check the reservation status.

USER: Can you please help me ? I am Justin Wilson.

ASSISTANT: There is no reservation found with your details, Justin.

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

ASSISTANT: Thank you for choosing us, have a good day.