You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Sandra Lewis, can you please help me in booking my flight ticket to DTW from IAD with the normal-cost airlines?

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

USER: Sure, my planned trip dates are Apr 06 and Apr 08.

ASSISTANT: Is there any class preference for you?

USER: Yes, I need a direct flight for my journey.

ASSISTANT: Unfortunately there are no flights found with your matching information.

USER: Not an issue with that, anyways thank you for the information.

ASSISTANT: Thank you for choosing us.