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

ASSISTANT: Hello, how may I assist you?

USER: I would like to attend a conference in Las Vegas. So, can you help me book a direct flight?

ASSISTANT: Sure, I will help you, may I know your travelling dates, please?

USER: I intend to start on 12/24 and return on 12/26.

ASSISTANT: Could you please provide me your airport codes?

USER: My journey is from Houston, TX - IAH to Las Vegas, NV - LAS.

ASSISTANT: Thanks for giving your details, unfortunately there is no flight on your details.

USER: Ok. Thank you for your response.

ASSISTANT: Thank you choosing us. Have a good day.