Brushing teeth is not the answer.
Using the right toothpaste, not eating acidic foods as the first thing in the morning, enpigh space between the teeth and proper nutrition are what make healthy teeth.
Brushing excessively only destroy the protective layer of your teeth and makes them even more vurnerable to acid in fruits.
Also, don't do the "professional teeth cleaning" or whatever they call it in English every six months.
That is too frequent. That too ddestroys the protective layer. It can be regenerated, but requires time, IF the nutrition is good.
And btw, I brush my teeth VERY rarely.
Every second day, in before I go to bed. Just saying.
I could take photos of my teeth, but that could doxx me as well, so, unfortunately you will have to take my story with a grain of salt.