You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name please?

USER: I am Betty Smith.

ASSISTANT: Yes, how can I help you?

USER: My father planned for the trip, but due to health issue he changed the trip, so please help me to change the existing reservation.

ASSISTANT: Sure, please wait for a while.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation found by your name. Do you want any other information please?

USER: It's ok. No, thank you.

ASSISTANT: Thank you and have a nice day.