You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: My name is Donald Jackson.

ASSISTANT: Glad to meet you Donald.

USER: My friend has invited to attend a party at Las Vegas. Please help me in booking a ticket.

ASSISTANT: Sure, I will help you with that. Can I have your travel dates please?

USER: I am planning to travel on dates 07/31 and 08/02.

ASSISTANT: Ok, please let me know airport codes too.

USER: The airport codes are HOU and LAS.

ASSISTANT: Please wait a moment and I will check for flight availability.

USER: Sure, take your time.

ASSISTANT: Sorry Donald, no flight is available to you on your dates.

USER: That's fine, thank you for the information.

ASSISTANT: Thank you for choosing us, have a great day. My pleasure.