I have done this more than once by removing my number from their call list- but guess what- they use a different line to contact you from very similar to the ones I already removed from- VERY ANNOYING.

Didn't answer it here, and glad of that….

just called here. second ring I picked up, but they already hung up.

They called our office again but their call was blocked BEFORE they even robo-dialed my number.

How, you ask?

We have the Digitone Call Blocker.  The Digitone is wonderful in that it blocks numbers (as expected) but it can also block entire area codes!!!   We have had the 204 area code blocked for several months now - along with 44 other area codes - including the 202 area code.  Both DC area codes...
Best $100 I ever spent!