ADT deducting costs without Authorisation

On Tuesday 02.02.2016 when I checked my bank statements for debit order going off I noticed that there was two debits for ADT. One for R220.00 which is my monthly debit order and one for R200.64 which I did not know what it is for. When I contacted ADT regarding this amount they told me that it is for False alarms. When I asked since when do they charge for false alarms, I was told since last year. Never did we received any notification correspondence informing us that they will be charging us for false alarms. As I have not given any Authorisation for additional costs to be debited from my account by ADT, I've requested that the money must be paid back into my account. The response was put it in writing. I refuse to put this in writing as why must i go through all that hassle and they(ADT) just do what they want with out authorisation.