You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am planning to visit Lady Bird Lake at Austin, could you please help me with booking a flight ticket from IAH to AUS?

ASSISTANT: Sure, can I know the travel dates please?

USER: I would like to depart on Jan 4th and return on Jan 6th.

ASSISTANT: Do you have any requirements?

USER: Make sure that my depart time must be afternoon.

ASSISTANT: May I know your name please?

USER: I am Patrick Johnson.

ASSISTANT: Sorry, there are no flights available as per your request. Thank you for approaching us.

USER: Ok, not an issue. Anyways, thank you for the information.