Harrassment over debt not owned - very rude

I constantly receive calls from Norman Bisset and Assoc with regards to debt I do not owe to them. They claim that I have a cheque account with Standard bank and that I still owe money on the account and must pay immediately. The more I try to explain that I do not have a cheque account with Standard bank, the more rude and threatening they are towards me saying that I must pay the amount owed.<br> I am being called on all of my cellphone numbers I have, some of which belongs to other members of my family and they are also plagued by these calls. Everytime I explain to one person the whole situation, not even 5 minutes after the one call, I receive another call from another person at the same company with regards to the same thing. They say the did put comments on their system, but clearly there is no communication between them as the one does not know what the other one does. They are very unprofessional and we find it very annoying. I have reported them to the NCC and are awaiting outcome thereof as we can not allow them to harass us any longer. If need be, legal action will be instituted against this company.