I have a portable phone/answering matching on landline with me DSL bundle. I kept getting this call from India about credit card problems even though I dont own a credit card, my credit is sooooo bad I destroyed it when I was 18 and got sued by banks which I never showed up or paid and since I own no assets they wasted money suing... Now I'm in my 40s
Anyhow the trick to stop the shit India calls coming in 4 and 5 times per day was sadly be as offensive and racist and vile and shocking as possible, become a Chan kid as if they od'd on Ritalin hehe
I had some chick get so mad she was screaming at me in a foreign language, the a supervisor took over her call and acted as ic was going to apologize, so I blasted him with racist to sexual to US outsourcing call centers so they can make 50 cent an hour blah blah. He got to yelling in his own language, I kept having fun looking up how to give death threats and rape daughters in their language. The line goes dead ....
Its now been a year and 2 months and my phone has not range once except for my family and occasional doc appt reminder
Go nuts and go the sicker the better, it works and you'll enjoy the cathartic moment of destroying them to the point they start screaming some foreign gibberish while you laugh and know them dumbasses won't call you ever again.