You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: Can you please help me to modify my reservation to other dates?

ASSISTANT: Sure, may I know your name please to check further?

USER: Sure, my name is Michelle Harris.

ASSISTANT: Please stand by.

USER: Sure.

ASSISTANT:  Sorry, no reservation found on your given name in our database to modify it.

USER: No issues, thank you.

ASSISTANT: Thank you for contacting us.