I've been getting calls for 4 years from debt collectors for someone else. Not for my debt, but for someone else's debt and legal troubles. So when telling th

I've been getting calls for 4 years from debt collectors for someone else. Not for my debt, but for someone else's debt and legal troubles. So when telling them to stop calling me hasn't worked, what can I do? It's 4 years now, and anyone calling for the old person at this point is being negligent.