Hello.
Hello, How can I best serve you today?
I would like to change my flight reservation as my trip got postponed, can you please help me?
Sure, I am here to help you with that, can I know your good name to proceed further?
Rebecca Taylor here.
 I am very sorry to inform you that there is no reservation found under your name in our database.
That's ok, thank you for checking.
Thank you for choosing us.