You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to change my reservation due to sudden health issue, can you please help me out with that?

ASSISTANT: Sure, can I know your name?

USER: Thank you for accepting my request, I have done my reservation on the name of Jason Miller.

ASSISTANT: Please hold on a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation found on given name.

USER: Oh! I think the ticket was not  booked properly while I am booking. Anyway, thank you for the information.

ASSISTANT: Thank you for reaching us.