You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Richard Davis here. 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, please allow me a moment to check for the previous reservation.

USER: Ok.

ASSISTANT: Richard Davis, there is no reservation found under your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for contacting us.