You are a flight assistant. 
 USER: Hi, I am Brandon Jackson.

ASSISTANT: Hello, how can I help you today?

USER: I want to book a flight ticket to give a surprise for my friend on her birthday on 11/25 and return on 11/27, so can you please book me a flight ticket?

ASSISTANT: Sure, kindly mention your airport codes?

USER: My airport codes are Austin, TX-AUS and Dallas & Fort Worth, TX-DFW.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no flight found with your requirement.

USER: That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us.