No authority to debit my account

Showmax are the biggest ****** you can ever encounter, i never siged any document for them to debit my account, I was paying via EFT and they just started debiting my account daily, now I'm being told I am not legibile for a refund but who gave you authority to debit my account. You even faild to show me where i signed up for a debit order. You are ****** and i want my changres refunded. i used you live chat facility usles, spoke to Malebo she is clueless shame and her manager and Lungile