You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Due to some client meeting, I am willing to change my reservation. Can you please help me for this?

ASSISTANT: Sure, I will help you to change your reservation.

USER: Thank you very much for quick access.

ASSISTANT: Please mention your good name?

USER: Myself Brian Phillips.

ASSISTANT: Please wait for a moment, while I search for your reservation.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: Not a big issue, anyhow thank you very much for your service.

ASSISTANT: Thank you for reaching us, we hope see you again.