You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Christopher Wilson.

ASSISTANT: How can I assist you?

USER: Actually I made a earlier reservation to go for a trip with my friends, but due to heavy work load in office I want to change my reservation. Can you help me?

ASSISTANT: Ok, please wait I will revert you in a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that no reservation was found on your name.

USER: That's Ok, thanks for your response.

ASSISTANT:  Thank you for availing us.