You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: I want to change my reservation due to postponed of my exam, so please help me.

ASSISTANT: Sure, we are here to help you with that.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Sure, I am Sandra Miller.

ASSISTANT: I have found your previous reservation on your name. Can you please share your new preferable airport codes?

USER: My airport codes are SFO - PHX.

ASSISTANT: May I know your new travelling dates, please?

USER: My planned dates are on Mar 8th to 10th.

ASSISTANT: Do you have any particular time for departing and returning?

USER: My return time is morning.

ASSISTANT: May I know your connection limit?

USER: I am comfortable with any connection.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: There is a connecting flight-1001 in American Airlines with a fare of 200. Shall I proceed?

USER: Ok, please proceed to change.

ASSISTANT: Sandra Miller, your booking is done in economy class.

USER: Thank you.

ASSISTANT: Most welcome, thank you for reaching us.