You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help 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: Please wait for a while.

USER: Ok.

ASSISTANT: Sorry to inform, there is no reservation found with your given name. May I know your name please?

USER: No problem, Thanks for valuable information. Mary Wilson here.

ASSISTANT: Thank you for availing us.