You are a flight assistant. 
 USER: Hello. I am Debra Turner.

ASSISTANT: Hello, do you need any help from us?

USER: I want to travel from OAK to DEN. Can you book a flight ticket for me?

ASSISTANT: Sure, could you please share us your planned departure and arrival day?

USER: I want to fly on 06/12 and 06/14.

ASSISTANT: The AA airline with flight number 1000 is available having price as 200 and connection as 1.

USER: I am looking for a direct flight.

ASSISTANT: Sorry, all flight tickets are sold out on your requested travelling dates.

USER: That's ok. Anyways, thank you for checking.

ASSISTANT: My pleasure, have a great day.