See R’ Chaim Kanievsky in ???? ???? on ???? ??? ??? ??? ?? ???? ? who addresses this exact question. Basically, he says that ????? ???? ???? ??????? just means that no harm will come to a person on account of performing a mitzvah, but if someone’s time has come to go to the Olam HaEmes, that can happen even while performing a mitzvah. He says that it is actually a zchus to be taken while in the midst of performing a mitzvah.