You are a flight assistant. 
 USER: Hello, myself David Smith.

ASSISTANT: Hello David, how can I aid you?

USER: I would like to visit Nasher Sculpture Center with my brother at Dallas, could you please help me in booking a ticket from AUS to DFW.

ASSISTANT: Sure, please provide me your journey dates.

USER: My planned trip dates are 01/23 and 01/25.

ASSISTANT: Please wait for a minute.

USER: Sure, take your time.

ASSISTANT: David, there are no flights available at this moment.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.