Call blocker stopped working

I have used Call blocker for years to prevent misuse of my landlines. Acc ***. Last two months cellphone calls started appearing on statement and my costs have jumped , I then checked Call blocker and noticed it wasn't working as I can call any mobile number from it. I have tried to get hold of correct dept at Telkom, with no luck. Have reached out on Twitter, and was happy to be told it was being looked into but 3 days later and still have no feedback and Call blocker not working even though it's activated. It really disappoints to have to resort to logging complaints to get help which should I shouldn't have to beg for. Please get this resolved , once and for all.