You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: As part of my schedule the client meeting has postponed, can you change my existing reservation.

ASSISTANT: Sure, we are glad to help you. Please wait for a moment.

USER: OK.

ASSISTANT: Thanks for your patience. Sorry, we did not find any existing reservation based on your name.

USER: I am Patricia Campbell.

ASSISTANT: Ok, Patricia Campbell, Thanks for choosing us.

USER: Thanks for your response.