(19) باب السَّهْوِ فِي الصَّلاَةِ وَالسُّجُودِ لَهُ
Abu Huraira reported:
The Messenger of Allah (ﷺ) said: When any one of you stands up to pray, the devil comes to him and confuses him to that he does not know how much he has prayed. If any one of you has such an experience he should perform two prostrations while sitting down (in qa'da).
Reference: Sahih Muslim 389 f
In-book reference: Book 5, Hadith 103
USC-MSA web (English) reference(deprecated numbering scheme): Book 4, Hadith 1159