You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I best serve you today?

USER: I want to book a flight ticket to Philadelphia PA-PHL, help me in booking my flight ticket from Denver CO-DEN.

ASSISTANT: Sure, Can you please let me know your travelling dates?

USER: My starting date is on 02/26, I will return to Denver on 02/28.

ASSISTANT: Do you prefer any way station in between journey?

USER: No, I need a direct flight.

ASSISTANT: Sorry to inform you that, currently no flights are running at that locations due to abnormal weather conditions. May I have your name please?

USER: Ok, I will go with the other alternative.

ASSISTANT: Ok.

USER: Any I am Gary Martinez.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your effort.