The World Federation One Stop Fiqh

Ruling 1206

If after performing ṣalāt al-iḥtiyāṭ one realises that the deficiency in the number of rakʿahs in his prayer was less than the number of rakʿahs in his ṣalāt al‐iḥtiyāṭ – for example, for the doubt between two and four rakʿahs, he performs two rakʿahs of ṣalāt al‐iḥtiyāṭ and later realises that he had performed three rakʿahs – in such a case, he must perform the [original] prayer again.