Narrated Abdullah ibn Jafar: The Prophet ﷺ said: Anyone who is in doubt in his prayer should make two prostrations after giving the salutation.
Related hadith on this topic
Explanation & Benefits
Shaykh Umar Farooq Saeedi
1033. Commentary:
That is, after completing their respective rak‘ahs, they should perform two prostrations (sujood) at the end, and from this hadith it is understood that the prostrations of forgetfulness (sujood as-sahw) can also be performed after the salutation (salaam). However, according to other scholars, this narration is weak. See: [الموسوعة الحديثيه۔ مسند احمد محقق 276/3]
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 1033
Hafiz Muhammad Ameen
1252. Commentary: The narrations from Hadith 1246 to 1252 are concise. To correctly understand their meaning, one should seek help from the detailed narrations mentioned above them; that is, in the case of doubt, after ascertaining the correct matter or relying upon the lesser (number), one should complete the prayer. Then, after saying the salam, perform two prostrations of forgetfulness (sujud as-sahw) and then say the salam again. See: [صحیح مسلم ، المساجد ، حدیث : 572]. In the case where more units of prayer have been performed, only two prostrations are sufficient.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 1252