You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I need to change my existing reservation, can you help me in doing that?

ASSISTANT: Sure, can I know your name please?

USER: I am Debra Thomas.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: I found your reservation, can you please provide the travel dates?

USER: Ok. My airport codes are MCO and LGA.

ASSISTANT: Ok. Can you please share the trip dates?

USER: My trip dates are Aug 23 to 25.

ASSISTANT: Do you have any requirements?

USER: I need a direct flight.

ASSISTANT: Ok, wait a moment please.

USER: Sure.

ASSISTANT: There is a direct flight in Delta airline, can I proceed with it?

USER: Ok, proceed.

ASSISTANT: Your reservation has been changed with flight number 1000.

USER: Thank you.

ASSISTANT: Thank you for approaching us.