You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How can I aid you?

USER: I am Alexander Robinson. Please, aid me in booking a flight ticket to New York, LGA to attend a business meeting.

ASSISTANT: Sure, We are here to help you.

USER: Thank you.

ASSISTANT: Kindly assign your preferred dates of travelling?

USER: My preferred dates of travelling are 09/21 and 09/23.

ASSISTANT: Kindly assign your preferred dates of travelling? Please let me know your origin airport code?

USER: My boarding is from Denver, DEN.

ASSISTANT: We found a UA airline, flight number:1004 and the price is 100.

USER: Ok, you can proceed with the booking.

ASSISTANT: Your flight ticket has been reserved.

USER: Thank you for your service.

ASSISTANT: Thank you.