Netstar continues

I've been calling netstar for some months now to correct my problem and they didn't. Last time I complained about the issues on this platform, their manager called me and all was corrected according to him. Now three months later the third-party sent me letter of Demand for R145 for another car now and it is no longer yhe Polo they claimed I registered with them. It is so annoying and I've canceled that car long time ago in Jan but still shows o their systems.