Hello, I am David Clark.
Hello, how may I support you today?
I want to cancel my recent reservation due to some issues, can you please help me with that?
Sure, we are here to help you. Please hold a moment.
Ok.
Thank you for your time, we have  found  a reservation with your name. Shall I proceed to cancel.
Ok, please cancel it.
Sure, your ticket has been cancelled.
Thanks for your service.
Thank you for availing us.