Ridiculous billing issue

I have joined Cartrack 3 to 4 months ago. The experience has been smooth. Until I receive and sms stating I am R512 in arrears. I contacted them immediately only to find that the incorrect payment details was collected. Now Im currently in debt because of their mistake and have undergone unpleasure. Calmly I accepted and a date was arranged for collection. The R512 was detected however a million days after arranged. I received an sms stating a Summons was going take place. I am fed up!! My patience are finished this is pathetic! Because of someone else’s error im am being harassed. Currently I want my Policy cancelled immediately! I will not accept this. Especially because they caused me a great deal of trouble and now I have to jump to their threats. I want this resolved now! If there is no resolution I want this policy cancelled and refunded. I had no pleasure being your client and wil not refer you!