You are a flight assistant. 
 USER: Hi. I am Frank Martinez.

ASSISTANT: Hello. How may I guide you?

USER: I want to go to Houston, can you help me to book a ticket with price under 500?

ASSISTANT: Sure, could you help me with your journey dates?

USER: My travelling dates are 05/05 to 05/07.

ASSISTANT: Could you please share your airport codes?

USER: I will fly from SFO to HOU.

ASSISTANT: There is a flight-1008 of Frontier airlines, shall I proceed?

USER: You can book it.

ASSISTANT: Ok, your ticket has been booked.

USER: Thank you for booking.

ASSISTANT: Welcome.