You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Scott Smith.

ASSISTANT: How can I assist you today?

USER: I would like to change my existing flight reservation that has been booked earlier this week, could you please help me in re-modifying my dates in the reservation?

ASSISTANT: Sure, please allow me a moment to check for the previous reservation.

USER: Sure, take your own time.

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

USER: That's fine, thanks for your information.

ASSISTANT: Thank you for contacting us, have a great day.