My Tech Zone and One World Telecoms Pty Ltd are ****mers, please I want my money back

Three months back I received a call from my tech zone offering me a loan that comes with benefits of getting a data every month and they made a debit order of R140. That whole amount Is being deducted every month from my bank account but I never received any benefits from them and when you try to call them they don't pick up their phones. I need help for the debit order to be stopped by them because the bank can't I've tried so many ways...My Tech Zone and One World Telecoms Pty Ltd are ****mers please I want my money back