Hello, this is Donna Hernandez.
user
Hello, how can I assist you?
assistant
As part of my schedule, I have booked flight ticket to attend business meet in the month of July. unfortunately the meeting got postponed to next month so, I want to change my existing reservation. Can you help me in changing reservation?
user
Ok, but according to  your name we do not have any flight reservation to change.
assistant
OK, thanks for providing information.
user
Thanks for contacting us.
assistant