Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: I heard the Prophet (peace and blessings be upon him) say: "Satan comes to one of you while he is performing prayer. He comes so that he may make his prayer doubtful for him, to the extent that a person does not know how much he has prayed. When someone faces such a situation, then when he is sitting, he should perform two prostrations of forgetfulness (sajda sahw)."