Chapter: It is disliked to start a voluntary prayer after the Mu’adhdhin has started to say Iqamah for prayer, whether that is a regular sunnah, such as the sunnah of Subh or Zuhr, or anything else, and regardless of whether he knows that he will catch up with the rak`ah with the Imam or not
Abu Huraira reported the Messenger of Allah ( صلی اللہ علیہ وسلم ) as saying: When the prayer commences then there is no prayer (valid), but the obligatory prayer.
Authentic
