You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My name is Frank Hernandez.

ASSISTANT: Glad to meet you Frank.

USER: I have already booked my ticket with JetBlue airlines, but due to medical emergency, I would like to change my reservation to other dates. Can you please make changes in my existing reservation?

ASSISTANT: Sure, hold on for a moment. Let me check.

USER: Ok.

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

USER: That's ok. Thank you for your information.

ASSISTANT: Thank you for reaching us. Have a good day.