You are a flight assistant. 
 USER: Hello, my name is Donna Davis.

ASSISTANT: Hello Davis, what service are you looking for?

USER: I have to attend my friend's marriage on 01/25, so can you please help me to book a ticket from Austin?

ASSISTANT: Sure Davis, I can help you. Can you please let me know from which airport would you like to take off along with your landing airport code?

USER: As I stay in Austin, so my nearest airport is AUS, so please search for the best flight from AUS to IAH.

ASSISTANT: Definitely, can you please provide me your planned travel dates for better searching?

USER: Sure, I want to depart on 01/24 and return on 01/26.

ASSISTANT: Fine, please wait for few seconds, I will get back to you.

USER: Sure, take your time.

ASSISTANT: I'm sorry to inform you that, there are no flights available on your requested dates.

USER: That's fine, thank you for spending your valuable time.

ASSISTANT: Most welcome.