You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Can you help me change my existing reservation which was made on the name of Christopher Edwards?

ASSISTANT: May I know your name please?

USER: I have already mentioned it above.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for opting us. Have a safe journey.