You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I want to change my existing reservation, due to bad weather conditions. Can you please help me to change reservation?

ASSISTANT: Sure, I am happy to help you out.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: I am Margaret Allen here.

ASSISTANT: Ok, please give me a moment. Let me check your previous reservation status.

USER: Ok, sure. I will wait for your response.

ASSISTANT: We are happy to inform you that, there is an active reservation found on your name. Please share your airport codes.

USER: That's very happy to here from you. BOS and LAS are my airport codes.

ASSISTANT: Ok, let me know your preferable travelling dates.

USER: My planned travelling dates are Oct 16th and Oct 18th.

ASSISTANT: Do you have any connection limit?

USER: I prefer a single connecting flight.

ASSISTANT: May I know your class preference?

USER: I prefer to travel in economy class.

ASSISTANT: Do you have any other requirements?

USER: I don't have any more requirements.

ASSISTANT: Ok, please be on hold.

USER: Ok, sure.

ASSISTANT: Sorry, there are no flights in route as per your travelling details.

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

ASSISTANT: Thank you for reaching us.