Pensioner's vehicle excess increased from R0.00 to R3500.00 because of one accident whilst the driver was innocent.

I have had a short term insurance with Santam for a couple of years now. In 2020 (December) my son had a car accident where a bakkie collided into the back of his vehicle, whilst he was stationary at a red robot. Santam has since recouped the amount of the claim from the other driver. In February 2022 my car was hit at the side by a truck whilst I was stationary behind other cars as the robot was not working. Driver claimed he did not see me. As I was stationary with cars in front of my and a solid wall holding up a railway bridge to my left. Now Santam has decided to increase my excess on two vehicles from R0.00 to R3500.00. Us as policy holders are held hostage by the insurance companies when accidents occur through no fault of the drivers. Why? I am of pensionable age and drive very carefully, so why am I being punished? My son's car is on my insurance as he lives with me. It's time the insurance industry is investigated!