You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. 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: May I know your name please?

USER: Sure, my name is Cynthia Hernandez.

ASSISTANT: Sure, please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation matching with your name in our portal to make changes further.

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

ASSISTANT: Thank you for reaching us.