You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you?

USER: I made a reservation earlier to visit museum of fine arts. Due to emergency health issue I want to change my existing reservation. Can you help me in changing?

ASSISTANT: Sure, may I know your name?

USER: My name is William Young.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for opting us.