You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Samantha Young.

ASSISTANT: How can I assist you at this moment?

USER: Can you help me for changing my existing reservation?

ASSISTANT: Sure, I am happy to help you with that.

USER: Thank you.

ASSISTANT: Please be hold on for a moment.

USER: OK.

ASSISTANT: Yes, I have found your reservation so please provide me airport codes of your journey locations.

USER: My new airport codes are DFW to JFK.

ASSISTANT: Ok, please let me know your travel dates please.

USER: My travelling dates are 11/18 and 11/20.

ASSISTANT: Please wait a moment and I will inform you flight details soon.

USER: OK.

ASSISTANT: Yes, I have found a flight in Spirit airlines with connection 1 and price 100, is it ok for you?

USER: Yes, I am ok book it.

ASSISTANT: Ok Samantha Young, I have confirmed a ticket with flight number 1019.

USER: Thank you for booking.

ASSISTANT: Thank you for choosing us.