You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Due to some urgent office meeting at Austin, I am planning to change my reservation. Can you please help me for this?

ASSISTANT: Sure, I will help you with that.

USER: Thank you very much for quick access.

ASSISTANT: May I know your name please?

USER: Myself Stephen Robinson.

ASSISTANT: Please wait while I find your existing reservation.

USER: Sure, I will wait for your response.

ASSISTANT: I am unable to trace your reservation in our list.

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

ASSISTANT: Thank you for reaching us.