The Messenger of Allah ﷺ commanded me to announce that prayer is not valid but with the recitation of Fatihat al-kitab and something more.
أَمَرَنِي رَسُولُ اللَّهِ ﷺ أَنْ أُنَادِيَ أَنَّهُ لاَ صَلاَةَ إِلاَّ بِقِرَاءَةِ فَاتِحَةِ الْكِتَابِ فَمَا زَادَ