You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Rachel Hernandez. I have to attend dance competition at Houston, can you please help me to book a flight ticket from DEN to HOU?

ASSISTANT: Sure, may I know your travel dates?

USER: Sure, my travelling dates are Jan 14 and Jan 16.

ASSISTANT: At what time do you like to travel?

USER: My departing time is afternoon.

ASSISTANT: We found a economy flight on your details with Frontier Airlines, flight number: 1007.

USER: Ok, please proceed.

ASSISTANT: I am sorry to say that there is no flight at afternoon time.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you.