ADT debit order theft!!!!

I have been a customer of ADT for some years now and i have had my alarm upgraded with sensors added to the sum total of R7886,99 and upon signing the deal with the rep it was agreeded that a 50% deposit was required before installation which we paid immediatley and then the balance would be split over 2 payments over the next 2 months. Low and behold i then recieve an email from Neil Bowers at ADT telling me they have my deposit of R3943.50 but now require the balance and want me to EFT. I then exaplain to Neil the terms of the agreement and Neil says nothing, only for me to wake up on Saturday and have the amount of R7886,99 deducted from my account!!! Of course the rep is shocked and ofcouse she can only follow up on Monday ( Being today) I the customer then have to call Neil to find out what happened then follow up with him again only to be told I sent your refund for authorisation and I can only have your money back on Wednesday!!!! this is completely unaccepable. Not only did ADT ***** more money than they were permitted to debit from my account now I must SING for my return!!!! uttter disgrace in service from ADT!!!! I then call Neil again who gives me his managers number Mr Tommy which DOES NOT WORK and i think ADT now thinks this is a joke!!!! I want my money BACK IMMEDIATELY!!!! NOT tomorrow, not WEDNESDAY, NOW!!!!!!