How to stop sales calls

This morning I got a call from Comcast. They were selling me some shit I wasn’t interested, so I let the caller know as much:

salesperson – Good morning sir, may I speak to Myron Parks?
me – Yes.
salesperson – may I ask who I am speaking with?
me – Myron Parks.
salesperson – Good morning sir, this call may be recorded for quality purposes.
me – …
salesperson – If I have your permission I would like to let you know that Comcast Voice is available in your area.
salesperson – And I would like to let you know that youqualifyforadiscontandIwouldliketo
me – Actually, you don’t have permission to talk to me about that.
salesperson – …
me – This conversation is over.
salesperson – Okay, thank you and have a nice day sir.