You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I have a plan to change my existing reservation to some other dates. Can you help me?

ASSISTANT: Sure, may I know your name please to check your reservation status?

USER: My name is Jessica Martinez.

ASSISTANT: Please hold on a moment.

USER: Ok.

ASSISTANT: Jessica, no reservation has been found on your name in our database.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for choosing us.