3 years of unwanted harrasing calls

for over 3 years they have called us, normally in the morning, we have logged 600+ calls by them and tried blocking them 200+ times(the number comes up as San Fernando. When we ask them to stop sometime they are nice sometime they are rude, and a few time they have told us they know where we live, and will come by and kill us!!!!!!!!!!!!!!!..we have filled 20 +complaints..