You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

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

ASSISTANT: Sure, we are here to help you.

USER: Ok.

ASSISTANT: May I know your name to proceed further?

USER: Timothy Davis is my name.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Thank you for your valuable time, sorry no reservation found with your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for availing us.