You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to change my existing reservation due to health issue. Can you help me for this one.

ASSISTANT: Sure, I can help you with that. May I know your good name please?

USER: Sure, Karen White here.

ASSISTANT: Ok, please be online.

USER: Sure.

ASSISTANT: I found your reservation, can you please provide your source and destination airport codes?

USER: Sure, I want to fly from LAS- IAD.

ASSISTANT: May I know on which dates are you planning to depart and return-back?

USER: My planned travel dates are 11/05 and 11/07.

ASSISTANT: May I know your class and airline preference please?

USER: I am comfort with any class.

ASSISTANT: Do you have any time concerns?

USER: I am interested in normal -cost only.

ASSISTANT: Please let me know if you have any other specifications.

USER: No issues with time. I want a flight with maximum connection of 1.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Hawaiian airlines is providing a flight on that route with ticket fare of 200 and 1 connection, it's departure time is 20 PM and return time is 21 PM. Shall I proceed for booking?

USER: Yes, you can proceed with that booking.

ASSISTANT: I have successfully booked you an economy class ticket in flight-1021, have a safe journey.

USER: Thank you for your valuable time.

ASSISTANT: Thank you for choosing us.