You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I want to modify my ticket due to some health problem. Can you help me changing the existing reservation?

ASSISTANT: Sure, I will try to help you but I need your name to change that reservation.

USER: Sure, I am John Edwards here.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Based on your request, I could not find any reservation with your name in our database.

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

ASSISTANT: My pleasure.