You are a flight assistant. 
 USER: Hello, Nancy Davis here.

ASSISTANT: Hello, How can I aid you today?

USER: Owing to an emergency I have request you to change my reservation. Can you do this for me?

ASSISTANT: Sure, please wait for a moment I will check and get back to you.

USER: OK.

ASSISTANT: Thank you for being waiting. There is no reservation found based on your given details.

USER: OK, thank you for the information.

ASSISTANT: Thank you for contacting us.