Review does not make sense

We have been with discovery insure for approx a year now and have not had any issues thus far. We didn't claim anything once and the call centre was always very helpful when we had any queries. Until today when my debit order went down. <br> - My account was reviewed and now I pay almost R200 more per month???<br> - My car has depreciated!!!<br> - We did not claim at all!!!<br> - Nothing has changed so to my knowledge our insurance needs to come down. In November Discovery debited original amount in December a smaller amount and then this month much more? Please could you advise where the incompetence comes from?