You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: Due to some emergency I need to change my existing reservation, Can you help me changing my reservation?

ASSISTANT: Sure, I am here to help you to change that reservation but I need your name to check the reservation details.

USER: I am Richard Collins.

ASSISTANT: Please wait for a minute, let me check.

USER: Sure.

ASSISTANT: Thanks for your patience, based on your request there is no reservation previously in our database with your name.

USER: No problem. Thank you for the information,.

ASSISTANT: You are welcome.