Supersonic is the worst!

I have to say, as a former Executive at Internet Solutions, Liquid Telecoms and Link Africa, I have never seen anything quite like it when it comes to the ICT sector. Supersonic you are literally the worst company that I have ever dealt with. Period. I signed up with Supersonic when moving into my estate about 5 years ago. I then moved three years later (within the same estate) where I app**** for a line transfer. This happened but I was then double billed for about 6 months. It took me six months of begging and pleading to get the billing corrected down to one single line. I then had a credit of about 6k which I spent another 3 months (at least) trying to get back. Supersonic (after promising a refund into my bank account) then decided to offset future payments. I accepted that as I was just so fed up with dealing with their useless call in center. Billing resumed after about 5 months or so. Things carried on for a few months, but then I get cut off. I phone in, wait at least half an hour (every time you call - sometimes up to an hour) - to be told that I have not paid my bill. I then say I can see the debit orders have gone through without issue. I was then told to send through 3 months bank statements to prove that I have paid. I then had to print out 3 months statements and black out all my private debit orders and purchases so I can PROVE to Supersonic that I have paid. The line was then restored. Low and behold, about a month later I get an email stating that my line will be suspended due to non payment. At the end of my tether, I wrote back to the accounts department telling them to suspend the line as I cant deal with them anymore. I then sent a cancellation letter to *** - I got a response saying that I will have to wait 30 days. At this stage I could not have cared less. I was debited at the end of the month (which I expected) and thought that was the last of it. I then got debited again now. I cannot believe it. I then phone in again, wait forever, enter my ID number (as always) then when they eventually answer, what is the first question I get asked? What is your ID number. Brilliant. So I explain my situation - not the ladies fault so I tried to stay calm - she then tells me that my line has been suspended due to non payment! I told her that I cancelled my line at the beginning of Dec and that two debit orders have now gone through since, so in fact I have over paid. So I sit with a suspended line, that I paid for, a line that is still billing that I cannot use and a company that says I have not paid them. It is insanity.