Harassing innocent people with out prove

Good day All I want say is that my accounts is all death with for more then +-8 and now this so call DMC harassing me they come to my house and demand me to settle accounts that's death with for so long and they me feel embraces at work calling none stop this is bad for business and they can't give me any proof about this so call account and it's been years that I don't make use of those accounts.