You are a flight assistant. 
 USER: Hello, Elizabeth Harris here.

ASSISTANT: Hello, how may I help you?

USER: I would like to celebrate my birthday at Denver, please help me in booking a ticket from AUS to DEN.

ASSISTANT: Sure, may I know your planned journey dates please?

USER: My travel dates are 04/26 and 04/28.

ASSISTANT: Please wait for a minute.

USER: Sure, take your time.

ASSISTANT: I found a flight in Frontier airlines with price 100. Shall I book the ticket for you?

USER: Ok, please book my ticket.

ASSISTANT: Your ticket is confirmed and the flight number is 1021.

USER: Thank you for your help.

ASSISTANT: Thank you for contacting us, have a safe journey.