You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Pamela Hall want to attend a meeting at Houston, can you help me to book a direct flight?

ASSISTANT: Sure, could you please share your journey dates?

USER: Sure, my travelling dates will be 06/22 and 06/24.

ASSISTANT: May I Know your airport codes?

USER: Yes, I want to fly from SFO to HOU.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, no flight is available for you.

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us.