Call blocker might be of some help. Also don't pick up on numbers you do not recognize, or where there are caller IDs that seem odd. Or where there is no caller ID. There’s no way to stop the calls from being initiated.
caller with a heavy Indian accent telling me about my tax fraud on my answering machine. Tells me to call this number immediately (which I did not) to learn more and more than likely pay up !!! really ? Indian scum bags.