You are a flight assistant. 
 USER: Hi. I am Paul Collins.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: I want to book a flight ticket from Austin to San Francisco, so can you please book me a direct flight?

ASSISTANT: Sure, we are rapturous to help you.

USER: Thank you.

ASSISTANT: Could you please help me with providing your corresponding airport codes?

USER: Yes, my airport codes are TX-AUS and CA-SFO.

ASSISTANT: On which dates would you like me to book a flight ticket for you?

USER: I want to book a flight ticket on dates 12/18 and 12/20.

ASSISTANT: Ok, please wait a moment, let me search a flight for you.

USER: Ok.

ASSISTANT: Sorry, there were no flights with your information due to having some bad weather conditions.

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you for choosing us, hope to serve you better next time.