You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am planning a trip to DEN, where my boarding will be from OAK.

ASSISTANT: Sure, may I know your planned travel dates?

USER: My travel dates are as follows Aug 20 and Aug 22.

ASSISTANT: Do you want connecting flight or direct flight?

USER: I would like to travel by a single connection flight.

ASSISTANT: Can you please share your airline preference?

USER: My airline preference would be normal cost.

ASSISTANT: Do you have any other requirements?

USER: No, proceed for booking.

ASSISTANT: May I know your good name please?

USER: Sure, this is Raymond Taylor.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: No issue, thank you for your time.

ASSISTANT: Thank you for opting us.