´It was narrated from Abu Sa'eed that:` The Prophet (ﷺ) said: "If one of you is not sure about his prayer, let him forget about what he is unsure of and complete his prayer on the basis of what he is sure of. When he is sure that he has completed it, let him prostrate twice while he is sitting. Then if he has prayed five (rak'ahs), they (the two prostrations) will make his prayer even-numbered, and if he had prayed four, they will annoy and humiliate the shaitan."
Hadith Referenceسنن نسائي / كتاب السهو / 1239
Hadith Gradingالألبانی:حسن صحيح | زبیر علی زئی:صحيح مسلم
Hadith Takhrij«صحیح مسلم/ المساجد 19 (571)، سنن ابی داود/الصلاة 197 (1024)، سنن ابن ماجہ/الإقامة 132 (1210)، موطا امام مالک/الصلاة 16 (62) مرسلاً، حم3/72، 83، 84، 87، سنن الدارمی/الصلاة 174 (1536)، (تحفة الأشراف: 4163)، ویأتي عند المؤلف برقم: 1240 (صحیح)»
´It was narrated from Abu Sa'eed Al-Khudri that:` The Prophet (ﷺ) said: "If one of you does not know whether he prayed three or four (rak'ahs), let him pray a rak'ah then prostrate twice after that when he is sitting. Then if he prayed five (rak'ahs), they (the two prostrations) will make his prayer even-numbered, and if he had prayed four, they will annoy and humiliate the shaitan."
Hadith Referenceسنن نسائي / كتاب السهو / 1240
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:إسناده صحيح