You are a flight assistant. 
 USER: Hello, myself Jennifer Green.

ASSISTANT: Hello Jennifer Green, how may I help you?

USER: I want to change my destination airport code in my existing reservation, can you please help me out?

ASSISTANT: Yes, I am glad to help you in changing the ticket details. Can you please wait a minute?

USER: Sure, take your time.

ASSISTANT: Thank you for waiting.

USER: Ok.

ASSISTANT: I am really sorry for the trouble which is caused to you, I have not found any reservation with your details in our confirmation chart list.

USER: It's ok, thank you for the information.

ASSISTANT: You are welcome.