You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: My name is Debra Clark. My vocation holiday trip has been postponed. So, I am planing to change my existing reservation.

ASSISTANT: How are you Clark?

USER: I am doing good, thank you for asking.

ASSISTANT: Sure, please wait a moment.

USER: Sure.

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

USER: OK. Thank you for the information.

ASSISTANT: Thank you for reaching us, have a good day.

USER: Thank you. Have a great day.