Under what conditions are we allowed to do sajda sahw? (prostration of forgetfullness?)

Answer:

Sajda-e-Sahw becomes compulsory when one makes a mistake in a Waajib of Salaat.

and Allah Ta’ala Knows Best
Mufti Ebrahim Desai

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This answer was collected from Askimam.org, which is operated under the supervision of Mufti Ebrahim Desai from South Africa.

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