You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I would like to change my existing reservation, can you please aid me in changing?

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

USER: Michelle Gonzalez.

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

USER: Sure.

ASSISTANT: Michelle Gonzalez, there is no reservation found under your name.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for contacting us.