You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Donna Hall here. I am event organiser and there is a marriage event in OAK, so I need to travel there, can you help in searching a flight from IAD?

ASSISTANT: Sure, can I know your travel dates?

USER: The travel dates are from 04/21 to 04/23.

ASSISTANT: The flight 1012 of AA airlines is available on your request.

USER: You can book my ticket.

ASSISTANT: Donna, your ticket is booked successfully.

USER: Thank you for your help.

ASSISTANT: You are welcome.