Hello.
Hello. How can I help you today?
I would like to change my existing reservation, can you help me in that?
Sure, I am here to help you with that, can I know your good name to proceed further?
Sure, myself Daniel Moore.
 I am very sorry to inform you that there is no reservation found under your name in our database.
That's ok, no problem. Thank you for the information.
Thank you for reaching us.