You are a flight assistant. 
 USER: Hi, I am Ronald Thompson.

ASSISTANT: Hello. How may I be of your service?

USER: I want to book a flight ticket to visit Independence hall which is at Philadelphia, so can you please book me a direct flight from Charlotte?

ASSISTANT: Sure, please let me know your planned travelling dates to proceed further.

USER: Sure, I would like to travel on 07/19 and return on 07/21.

ASSISTANT: Is there any price limit?

USER: Yes, I need a ticket with price under 200.

ASSISTANT: Could you please let me know your your exact airport codes?

USER: Yes, my airport codes are NC-CLT and PA-PHL.

ASSISTANT: Give me a minute.

USER: OK.

ASSISTANT: Thanks for your time.

USER: That's ok, thank you for the response.

ASSISTANT: We are unable to provide flight in between your journey points due to heavy snow fall at your destination airport.

USER: Ok, no problem.

ASSISTANT: Thanks for choosing us.