Too frequent boxing problems in career mode

I envy you that you only have pitstop mistakes every 5 pitstops. i have bought upgrade that is supposed to result in mechanicks making less mistakes and since then every single pitstop there was mistake that is ruining my races. Its now aproximately 6 races since that upgrade and there were mistakes in pitstops in every race. its very very over the top and not realistic. i understand why it is there, but it needs to be balanced better. Its mega difficult to fight against overpowered AI that has tons of advantages against player and on top of that you have to deal with super frequent pitstop mistakes.