You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Alexander Williams here.

ASSISTANT: Williams, how can I assist you?

USER: I want to visit Austin Zoo with my family, so please book my ticket from Dallas.

ASSISTANT: Sure, I will help you. Can you please provide me your travel dates?

USER: My itinerary dates are 04/22 and 04/24.

ASSISTANT: Ok, please provide me your preferred airport codes.

USER: My genesis and terminus airport codes are DFW and AUS.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Flight-1005 is available with Frontier airlines and the ticket fare is 200 only. Is that ok for you?

USER: Go ahead to book my ticket.

ASSISTANT: Williams, your ticket is booked. Have a safe flight.

USER: Thank you for your expeditious service.

ASSISTANT: You are welcome and thank you for choosing us.