It doesn’t save anything into the database. The $model->save() returns with true, no error message when I try using getErrors(), also $model->validate() returns with true when I try to use it and $model->save(false) is the same output.
I also printed the $model->attributes after sending the form and it has the right values. The database table accepts the given values, I don’t get SQL error when adding the values manually.
Useful article, thanks, but I still don’t know how it could help me in this case. Maybe I’m just dumb, tried to play around the safe attributes a bit but the problem still occurs.
Finally solved. The problem was that I named the model "search" and somehow it might have encountered with the search function. As I renamed it to "user_search" it immediatelly worked properly. Thanks for your help tho.