A man of Juhaynah told him that he had heard the Prophet ﷺ reciting "When the earth is shaken" (Surah 99) in both rak'ahs of the morning prayer. But I do not know whether he had forgotten, or whether he recited it on purpose.  

أَخْبَرَهُ أَنَّهُ سَمِعَ النَّبِيَّ ﷺ يَقْرَأُ فِي الصُّبْحِ { إِذَا زُلْزِلَتِ الأَرْضُ } فِي الرَّكْعَتَيْنِ كِلْتَيْهِمَا فَلاَ أَدْرِي أَنَسِيَ رَسُولُ اللَّهِ ﷺ أَمْ قَرَأَ ذَلِكَ عَمْدًا