Hello.
Hello, could you please tell us for what help you approached us?
I want to change my existing reservation, can you please help me with this?
Ok, could I have your name please?
I am Christopher Young.
Ok, please allow me a moment.
Sure.
Sorry, there is no reservation with your name in our portal to make changes further.
Ok, no problem. Thank you for your information.
  You are welcome, have a great day.