More than 30% increase

Hi, I saw that my premium went up from 2019 to 2020 with more than 30%. On 2nd Jan my premium was R827.35 and on 1 Febr my premium was R1154.78. That is R327.43 increase. That is an increase of more than 30%! I send an email where I asked them to contact me. MiWay took more than a week to contact me. I explained to the person I was in a bad reception area and asked them to phone me back in 40 min, but I never got a call back.

It is just hard to understand that my premium went up by more than 30% while my vehicle's value obviously decreased? I know some Insurance Companies actually decrease your premium as the value of the vehicle decreases....