Hello.
Hello. What can I do for you today?
Can you please help me to change an exiting reservation?
Sure, may I know your good name please?
My name is Ronald Jackson.
Ok, please wait for few minutes.
Sure.
We found a reservation on your name. Can you please share your new travelling details?
Sure, my travelling dates are from 04/10 to 04/12.
Ok, provide your corresponding airport codes?
My airport codes are from DC-DCA to IL-ORD.
There are no flights available on your requested dates.
Ok, no worries at all.
Thank you for approaching  us.