Debit order without permission.

After noticing an unknown debit order on my account today, I called the bank anf they informed me it was from a company called Payment exchange. The bank reversed the debit order but said I had to call the conpany to prevent further deductions. The phone just rang every time I called. Then I googled the company...found lots of similar complaints. How do we stop these denit orders that go off without permission?? Can someone pls investigate the company.