You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I would like to visit my friend's house at Houston, IAH. I need your help in booking a ticket with the fare of 5000.

ASSISTANT: Sure, I am here to help you. May I know your travelling dates?

USER: My return would be on 07/16 and source is LAS. I need to start on 07/14.

ASSISTANT: Please wait for a while, I will check and get back to you.

USER: Sure.

ASSISTANT: May I know your name?

USER: My name is Brian Hernandez.

ASSISTANT: Sorry to tell that there is no flight found on your request.

USER: Ok, not an issue.

ASSISTANT: Thank you for  approaching us.

USER: Thanks for providing the valuable information.