COMPLAINT MIWAY INSURANCE

I was contacted by a MiWay agent and took out insurance from MiWay. Got a confirmation SMS to say that the debit date will be 2018-12-31. On 2018-12-24 the money was deducted from my bank account. I made contact with MiWay via there chat line whereby I was advised to reverse the debit order and send them the bank statement to be reimbursed with the banking cost. On 2018-12-28 I received an sms saying that a missed premium fee of R500 will be deducted when I have a valid claim as well as another sms saying that I do not have cover for the period 2018-12-31 to 2019-01-30. How can this company send you a confirmation with a certain date to it and change their debit dates and when you do as you where advised they want to deduct even more money.