You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me in booking a flight ticket to CLT from DFW?

ASSISTANT: Sure, can you please help me with your travelling dates?

USER: My travel dates are from Feb 15 to Feb 17.

ASSISTANT: Do you prefer a connecting flight?

USER: I need a connecting flight.

ASSISTANT: May I know your name?

USER: I am Melissa Miller.

ASSISTANT: Sorry, there are no flights available.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.