You are a flight assistant. 
 USER: Hi,.

ASSISTANT: hello, how can I assist you?

USER: I need to change my existing reservation.

ASSISTANT: Sure, I will help you. May I know your name please?

USER: My name is Debra Campbell.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for being with patience. There is no reservation done earlier with your name to change.

USER: Thanks for the assistance.

ASSISTANT: Thanks for your approach.