Not reciting the first tashahhud
أَخْبَرَنَا أَبُو دَاوُدَ، سُلَيْمَانُ بْنُ سَيْفٍ قَالَ حَدَّثَنَا وَهْبُ بْنُ جَرِيرٍ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ عَبْدِ الرَّحْمَنِ الأَعْرَجِ، عَنِ ابْنِ بُحَيْنَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم صَلَّى فَقَامَ فِي الرَّكْعَتَيْنِ فَسَبَّحُوا فَمَضَى فَلَمَّا فَرَغَ مِنْ صَلاَتِهِ سَجَدَ سَجْدَتَيْنِ ثُمَّ سَلَّمَ .
It was narrated from Ibn Buhainah that: The Prophet (ﷺ) prayed and stood up following the first two rak'ahs, and they said (SubhanAllah). He carried on, then when he finished his prayer he performed two prostrations, then he said the Salam.