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. (Using translation from Abū Dāʾūd 820)   

أَنَّ رَسُولَ اللَّهِ ﷺ «أَمَرَهُ أَنْ يَخْرُجَ يُنَادِي فِي النَّاسِ أَنْ لَا صَلَاةَ إِلَّا بِقِرَاءَةِ فَاتِحَةِ الْكِتَابِ فَمَا زَادَ»