3rd time being billed for calls not being made

in June I was being billed for phone calls which is not possible as I have no phone to make calls off of . There was a R500 bill within the first few days of June and Telkom said my lines have been crossed . A few weeks later they said the issue had been sorted out and I was credited with what I was billed for . Now I receive Julys bill and it's over R3000 !!! I still have no phone to make these calls yet I get the bill again ! Telkom assured me they had sorted the lines being crossed the first time around . And the worst part is that now if I don't pay this my Credit record will be affected ! Thanks Telkom for exceeding the expectations of how bad your service really is !