You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am William Thompson here.

ASSISTANT: How can I assist you at this moment?

USER: I want to visit Austin, can you please help me to book a ticket from IAD to AUS?

ASSISTANT: Sure, can you please provide your travelling dates to proceed further?

USER: Sure, my preferable planned dates of journey is from 03/27 to 03/29.

ASSISTANT: Wait a moment please.

USER: Sure.

ASSISTANT: Southwest airlines is available on this route with a ticket fare of 100, shall I book your ticket?

USER: Ok, please book it.

ASSISTANT: William Thompson, your ticket is booked with flight number 1001.

USER: Thank you for your help.

ASSISTANT: Thank you, have a safe journey.