You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, may I know your name to check for the previous reservation?

USER: Nancy Hernandez.

ASSISTANT: Please allow me a moment while I check for the reservation status.

USER: Sure.

ASSISTANT: Nancy Hernandez, there is no reservation found under your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for contacting us.