SA Unathi taking money from my account

SA Unathi have been taking money from my account for a number of months now and I don't know why. I first noticed it end of November 2015 but debits were made again in December and January 2016. Unfortunately I left SA in December and don't know who and how to contact anyone at SA Unathi. I have no recollection of any agreement with this organisation and what they are doing is *******.