You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Sandra Parker. I want to change my existing reservation due to postpone of my exams. Can you help me in that?

ASSISTANT: Sure, I am here to help.

USER: Thank you.

ASSISTANT: Please wait while I fetch your current reservation.

USER: Ok.

ASSISTANT: We have found your reservation, please share your new airport codes.

USER: My airport codes are LAX to IAH.

ASSISTANT: Please share your updated  travelling dates.

USER: I will fly on Jan 17 and return on Jan 19.

ASSISTANT: Do you have any other preferences?

USER: I need a connecting flight.

ASSISTANT: We have a flight from UA airline, number 1013 and the price is 100. Shall I proceed with the booking?

USER: You can proceed.

ASSISTANT: Your ticket booking is done in economy class.

USER: Thank you for your service.

ASSISTANT: Thank you for opting us.