You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: Sure, please help me with your name.

USER: Myself John Campbell.

ASSISTANT: Thank you. Please wait, let me check your reservation status in our database.

USER: Sure, I will wait for your response.

ASSISTANT: John Campbell, I have not found any reservation under your name in our database.

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

ASSISTANT: You are welcome and thank you for choosing us.