bmw dealer is the best place to have codes read and problems resolved .
i had same problem and diagnosis indicated left front wheel speed sensor so replaced sensor and no faults since . have since covered 8000miles .
there are other causes of these faults so have codes read and if left sensor indicated then you can swap left and right sensors then drive until fault occurs then read codes to see which sensor indicated , if right then it is sensor , if left then you know that sensor was good so something else causing problem .
some bmw techs post on this forum so they should give better advice than i could .