You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What assistance do you need from our agency?

USER: I just want to change my existing reservation, due to sudden change in meeting. Can you please assist me for modifications?

ASSISTANT: Sure, I am glad to help you with that. Could you please tell me your name to check the ticket status?

USER: Sure, please check my reservation on the name of Kathleen Jones.

ASSISTANT: I have found your past ticket in our records, can you please tell me your airport codes?

USER: Sure, my airport codes are OAK to reach my destination PHL.

ASSISTANT: Ok, may I know your departure and return journey dates please?

USER: My travelling dates are on Aug 19 and 21.

ASSISTANT: Ok, please tell me your preferences if any.

USER: I prefer an economy class.

ASSISTANT: Ok, do you have any connection limit requirement?

USER: No.

ASSISTANT: Ok, there is a flight with the connection limit 2 which is an economy class flight. This flight departs at 22:00 PM and returns at 22:00 PM. Shall I proceed with the ticket reservation process?

USER: Ok, please proceed for booking.

ASSISTANT: I have changed your travelling details in the ticket, the  flight number is 1005 in an American Airlines. Have a nice journey.

USER: Thank you.

ASSISTANT: Most welcome. Thank you for approaching us.