It was narrated from Umm Salamah that the Prophet (ﷺ) once prayed two Rak'ahs after 'Asr in her house. She asked him about that and he said:
"They are two Rak'ahs that I used to pray after Zuhr, but I got distracted and forgot them until I prayed 'Asr." (DE)
English reference (DE): Vol. 1, Book 6, Hadith 580 (DE)
Arabic reference (DE): Book 6, Hadith 586 (DE)