You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Dorothy Smith.

ASSISTANT: How can I assist you?

USER: Can you please help me to book a flight ticket from DFW to LAS?

ASSISTANT: Sure, May I know your travelling dates?

USER: The planned travel dates are Feb 1 and Feb 3.

ASSISTANT: Do you have any connection limit?

USER: I need a single connecting flight.

ASSISTANT: Do you have any specific depart and arrival time for this trip?

USER: The returning time of the flight should be in the morning.

ASSISTANT: Is there any class preference?

USER: No, I didn't have any other preferences.

ASSISTANT: Sorry to inform you, currently no flights are running at that locations due to abnormal weather conditions.

USER: It's ok, not an issue. Thank you for your time.

ASSISTANT: Thank you.