Fed up with this useless company

I would like to complain about cartrack again it seems these people they don't know their job . So few months ago I keep on receiving messages and calls from them claiming I owe them for one month. I requested that they send my statements because according to me I don't owe them, after that nothing was sent to me and they never received phone calls from them. This month when they try to debit my account on the 2nd there were no funds in my account then I made the transfer through the app they sent me on the 10th of R216 now I keep on receiving emails from them saying I owe them R217 when I reply to their emails telling them I don't owe them , they ignore it and keep on phoning me . I'm so fed up with this useless cartrack company.