Hi.
user
Hello, how may I assist you today?
assistant
I want to change my existing reservation. Can you help me for that one?
user
Sure, may I know your name please?
assistant
Sure, Linda Phillips here.
user
Please wait for a moment.
assistant
Sure.
user
There is reservation found as per your name, please share your recent  airport codes please.
assistant
Sure, my new airport codes are ATL and DEN.
user
May I know your planned travelling dates please?
assistant
My planned travel dates are 09/04 and 09/06.
user
If you have any other specifications please let me know, I'll check availability according to that?
assistant
I am comfortable with direct flight only.
user
Sorry Phillips, there is no flight found as per your travelling dates.
assistant