Angry and disappointed with the service

I'm very disappointed by the service of telkom. I took an insurance for my phone and I canceled it in December on the 05th last year. They told me about the 30 days notice. They deducted the amount again in January and I called to asked why and they told me it was going to be last debit as December did not include the 30 days notice. In February the same thing happened and I always have to find myself calling and enquiring about a bill that I canceled a long time ago. I have noticed that they have included the insurance premium again in my current bill. Please intervene. I'm tired of calling fhe office at all times and not be assisted. My numbers are ***. I look forward to hear from you soon.