You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Due to bad weather conditions, I want to change my existing reservation.Can you help me out?

ASSISTANT: Sure, I will help you with this. Please, provide me your name to check the reservation?

USER: Sure, my name is Gary Mitchell.

ASSISTANT: Sorry Gary, no reservation found on your name.

USER: Ok fine, thank you for the information.

ASSISTANT: Welcome, thank you for reaching us.