You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I would like to change my destination airport code, please help me in changing my existing reservation.

ASSISTANT: Sure, I am here to help you. May I know your name please?

USER: My name is Samuel Williams.

ASSISTANT: Ok, please wait a minute I will get back to you.

USER: Sure, take your time.

ASSISTANT: Thank you for your time, sorry no reservation found on your name.

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

ASSISTANT: Thank you for reaching us, have a nice day.