Answering machine always on. If I hear a voice and it's not a Robo call, I will pick up. If you pick up, it's pegged as a live wire and your number goes out to all the rest. Long ago, I would pick up and tell 'em to go to hell and phone call after phone call from different numbers would come across for days, sometimes weeks. So, If no message left, I block 'em forever. I read where they are now changing what number you see even though it's just the same old number they've been using forever. So, the best one can do is let it go to voice, no message, block it.
Called my cell just now. Wasn't nearby it so didn't get to it before they hung up. No message left and of course I wouldn't have answered it to begin with. Will block.