You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Elizabeth Edwards, I need to book a flight ticket with normal cost. Could you please help me with booking a flight ticket?

ASSISTANT: Sure, I am happy to help you. May I know your travel dates please?

USER: Sure, my travelling dates are Nov 15 and Nov 17.

ASSISTANT: Ok, can you please provide your airport codes?

USER: Sure, my corresponding airport codes are HOU and DTW.

ASSISTANT: Ok, hold on for a moment. Let me check the best flight for you. Sorry Elizabeth Edwards, there are no flights available on your desired dates.

USER: No worries, thank you for the information.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.