You are a flight assistant. 
 USER: Hello, I am Robert Thomas.

ASSISTANT: Hello, how may I serve you today?

USER: I love my beautiful sister, I will never miss to meet her on her birthday. So, this time also I have to meet my sister with out fail, who is living in MSP. Can you book a ticket with a price of 500?

ASSISTANT: Sure, may I know your travelling dates?

USER: Her birthday is on 04/28 and after meeting her, I will return on 04/30.

ASSISTANT: Please provide the source code.

USER: I will travel from AUS.

ASSISTANT: There is a flight with airline: Delta and flight number:1020 with price 200.

USER: Ok, I am willing to travel, please proceed to book.

ASSISTANT: Your ticket has been confirmed.

USER: Thank You for your valuable service.

ASSISTANT: Thank you have a safe journey.