You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I be your helping hand today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, we are here to help you to change your reservation.

USER: Thank you.

ASSISTANT: Please mention your name, to check with your previous reservation.

USER: My previous reservation has done with the name Anna Smith.

ASSISTANT: Thanks for providing your name, please standby.

USER: Sure.

ASSISTANT: We are happy to inform you that, we found a reservation on your name. Can you please provide your updated planned journey dates?

USER: My preferable journey dates are June 16 and June 18.

ASSISTANT: Ok, Kindly please share your travelling airport codes.

USER: My airport codes of journey are OAK and DFW.

ASSISTANT: Ok, May I know your connection limit?

USER: I prefer connecting flight for this trip.

ASSISTANT: Ok, please wait for a moment.

USER: Sure, I will wait for your information.

ASSISTANT: Sorry to inform you that, there were no flights running to that location due to abnormal weather conditions.

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

ASSISTANT: Thank you for choosing our service.