Unauthorised debit orders

Paytoza made debit orders on my account on behalf of three companies, that is CB Marketing , TA Marketing and Manhat Marketing. I've never entered into an agreement with these companies. I'm even struggling to get the contact details of these ********** companies from Paytoza. When I first called paytoza , they asked me to give them the reference number as they appear on the debit orders. Unfortunately at that time I only had one reference number for TA Marketing and they gave me their contact details but the phone doesn't go through. The lady (from paytoza) requested me to get the reference numbers for the other two companies and that she will call me back. After getting the reference numbers I decided to call paytoza again , since she did not call me back as she promised, but they put me on hold until I hung up. Does the paytoza not authenticate the debit order instructions from these companies , before making debit orders, don't they use signed debit order instructions? Now I have to spend more money on airtime trying to get hold of paytoza and its ********** clients.