ADT accounts department very poor service

My wife and myself have been ADT customers for many years. Always had great service. However, 2 weeks ago, an amount of over R 3000 was taken from my wife's bank account, additional to the normal debit order that is paid from her account every month. After many e-mails and phone calls, to various individuals, no feedback. NOTHING. We've sent them all the documents that they required but still no reply.