I am being harrassed for a prescribed debt

Out of the blue a few months ago I get a call from MBD Attorneys to tell me that there is an amount of about R180 outstanding on a municipal bill from Umfeleni Municipality. The house it is for was never on my name - it was my fathers house, who has since died, and I never had any link to those accounts! As far as I am concerned this should be a prescribed debt anyway, and they are threatening me now that I will be blacklisted if I do not pay this debt. I do not see how this is even linked to me. I can easily pay this amount of money but I refuse to do so as this is not my account. The call centre staff at MBD are rude, do not listen, start shouting and threatening me when I try and discuss this issue with them. They have phoned me several times since then and refuse to remove this off my name. I am at my wits end. I am contacting the Law Society about this too.