I am fed right up!

I keep getting phonecalls about getting my ducts cleaned.
I have told them I am not interested, and they call again...
I tell them not to call and they call again...
I've told them I don't have ducts and they still call.
I have gotten mad and sworn at them...
They call back.
You can't call the number back.
I am on the "Do NOT Call List"...it's useless.
I have call block on my  phone service and call block on my phones.
I can only block 12 numbers on my Bell service, I don't know how many I can block with my phone....I already have quite a few blocked.
Sooo...
I block their number and they still call.
They change the number they call from and call again.
I reported them to the CRTC.
I don't know if it will stop....
But I'm p*ssed off and not taking it any more!