You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

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

ASSISTANT: Sure, I will definitely help you in changing the ticket details. Can I know your name please?

USER: Myself Christopher Davis.

ASSISTANT: Ok, please give me a minute.

USER: Sure.

ASSISTANT: Sorry to intimate you that, when I have checked your ticket status, I didn't found any reservation with your name to change the ticket details.

USER: Not a big deal, anyhow thank you very much for checking the reservation status.

ASSISTANT: You are welcome. Thank you for consulting us.