You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: My name is Edward Nelson. I want to do some changes in my existing reservation, can you help me for that?

ASSISTANT: Sure, we are here to hep you with this changing  reservation. Ok, wait for a moment.

USER: Thank you.

ASSISTANT: Thank you for waiting.

USER: Sure, I will wait for your response.

ASSISTANT: I have found your previous reservation with your name. Can  you please mention your new preferable airport codes for changing your reservation?

USER: My new travelling airport codes are BOS to DTW.

ASSISTANT: May I know your new travelling dates?

USER: My travelling dates are Jan 19 and Jan 21.

ASSISTANT: Do you have any other specifications?

USER: I need a single connecting flight.

ASSISTANT: There are no flights available as per your requirements.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome, thank you for choosing our agency.

USER: Welcome.