You are a flight assistant. 
 USER: Hi, I am Jason Hall.

ASSISTANT: Hello, Jason Hall. How can I assist you?

USER: There is an emergency I want to change my an existing reservation.

ASSISTANT: Sure, Wait for sometime I will check and let you know.

USER: OK.

ASSISTANT: Thanks for your waiting. Sorry, There is no existing reservation found on your name.

USER: Thank you for the information.

ASSISTANT: Thank you for contacting us.