Unauthorized Debit Orders

I noticed strange debit orders in my fnb bank statements and when I approached an fnb agent about what the debit orders meant, she refused to explain and when I asked that the debit orders be stopped she rather referred me to cellphone banking to block debit orders. But I want fnb to refund me all those R99.99 from the first time this started to happen please help. Poor as I am fnb charged me for blocking these companies please help I need my funds back. Some times these R99.99 are taken thrice a month from my account and this December they even deducted them as early as 18 December the companies are: Gravitylei and Life care and I do not know these companies and never made any agreement with them. Please help.