Double billing for the past 6 months

During the first week of December 2015 I reported to Shyden that ADT has been double billing my account for the past six months . Promises were made that ADT will credit my account on the first Friday in December. This has now been going on for 5 weeks without ADT crediting my account. I have spoken to Shyden several times during the past 5 weeks and every time I am promised that the credits will be passed on the Friday following the phone call. When I phoned them again on Monday 11 January 2016 they said my account will be credited today, again they did not pass the credit through. There have already been over 40 complaints logged on Hallo Peter this month alone, with every complaint receiving the same, stock-standard reply. Since beginning of December I had to follow up with ADT without them returning any of my queries. I cancelled my debit order at the bank and my next option will be to go to the press, social media and any other means available to me. Your reply and resolution to this problem is expected without delay.