Unauthorised debit to my account

In November 2017 I paid my medical aid premium via EFT as always. However, on 01.02.17 Momentum (1 week later) debited my bank account with a premium which bounced due to no funds. Momentum informed me that cover was suspended. I wrote to them and advised that firstly, I was not impressed that I now had to pay a bank penalty for no funds, secondly, I did not sign a debit order for Momentum Health and thirdly, the bank account details they have are for my Dreaded Disease cover for which I did sign a debit order. Having my bank account details for another policy does not entitle them to willy nilly deduct monies which they think I owe them for another policy. Since these two policies are separate and are maintained separately, they need to stick to the terms and conditions of those separate contracts. No apologies were received. Low and behold, at the end of January, the same incident occurred, after I had emphatically explained to them their incorrect conduct. I paid my premium via EFT on 26.01.18 and they debited my account again on 01.02.18! This time there was enough money in my account for the unauthorised debit to go through. I wrote to them and asked them to UPDATE THEIR RECORDS accordingly. No reply / No apology / No refund of extra premium. I have now cancelled my medical aid with Momentum and plan to cancel the dreaded disease cover as soon as I can find an alternative. Come on Momentum! You can do better than that!