“Every prayer in which Fatihatil-Kitab (the Opening of the Book) is not recited, it is deficient, it is deficient.” (Using translation from Ibn Mājah 841)
قَالَ رَسُولُ اللهِ ﷺ كُلُّ صَلَاةٍ لَا يُقْرَأُ فِيهَا بِفَاتِحَةِ الْكِتَابِ فَهِيَ خِدَاجٌ فَهِيَ خِدَاجٌ فَهِيَ خِدَاجٌ غَيْرُ تَمَامٍ