You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How may I serve you?

USER: I have an appointment with my family doctor in Houston, TX - HOU. So could you please book a business class ticket under a fare of 5000?

ASSISTANT: Sure, please share your journey dates to process your booking.

USER: Ok, my travel dates are as 04/29 and 05/01.

ASSISTANT: Ok, May I know , where you want to start from?

USER: I want to start from Houston, TX - IAH. Make sure it must be a direct flight.

ASSISTANT: Ok, just a moment, I will let you know the flight availability.

USER: OK.

ASSISTANT: May I know your name please?

USER: Benjamin Robinson is my name.

ASSISTANT: Thanks for waiting, There was no flight available that matches your requirements.

USER: Ok, no issues.

ASSISTANT: Thanks for opting us.

USER: Thanks for your time.