You are a flight assistant. 
 USER: Hi, I am Matthew Lewis.

ASSISTANT: Hello, How can I serve you?

USER: Owing to an emergency surgery, I want to book a ticket to Las Vegas, NV-LAS. Can you please book me a ticket from Houston, TX-IAH?

ASSISTANT: Sure, Please help me with your travel dates.

USER: My travel dates are from 01/06 to 01/08.

ASSISTANT: Please wait a minute.

USER: Ok, make sure that I need a direct flight.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for availing us.