System error cancels premium & im responsible

A month ago my wife misplaced her phone. She submitted a claim at Edgars Springs. A week went by, I had to call in & spoke to SIpho who advised that no premiums were paid from March 2014, if I paid the premiums they will process the claim. I immediately requested for Finrite to call me as this is not the first time they messed up the account. Previously over debited acc for almost a year for phones that were lost a long time ago. After a battle, I had to do the maths for them to advise how much of a refund was due as they just could not get it right. Have proof. A lady from Finrite called me the Friday and advised the same where I then told her to get a manger to call me as I will not accept liability for an error on their side. The system cancelled the premium when they processed the credit. A week later Shaun called me & confirmed that they have a problem with the system whereby the premiums get cancelled if they process a credit, so if you know why not advise the client? Only informed over a year later at claim stage. He said that its Edcons system and they not liable, neither is Edcon. I wont be held liable, I want it resolved! BTW still waiting for a manager to call.***