You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you please help me to book a flight from PHL to SFO?

ASSISTANT: Sure, may I know the travelling dates?

USER: Sure, I want to travel on Jan 20 and need to return on Jan 22.

ASSISTANT: Do you have any connection limit?

USER: I need a flight with single stopover.

ASSISTANT: May I know your name?

USER: Mark Roberts here.

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

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you for opting us.