You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello. How can I assist you?

USER: Can you please help me in booking my flight ticket from DFW to HOU?

ASSISTANT: Can I know your travelling dates?

USER: My travelling dates are Dec 21-23.

ASSISTANT: Please let me know your connection limit?

USER: I would be comfortable with single stop over.

ASSISTANT: Do you have any other preference?

USER: No more preferences.

ASSISTANT: May I know your name please?

USER: Myself, Debra Martin.

ASSISTANT: Sorry, no flights available on your route.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.