What is the ruling on placing an legislated recitation in the wrong location during prayer when done unknowingly?

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This category includes reciting established supplications in inappropriate positions, such as reciting in *ruku'* or *sujud*, reciting the *tashahhud* while standing, reciting the *Salat 'ala an-Nabi* (blessing upon the Prophet) in the first *tashahhud*, or reciting an extra surah in the final units of a four-rak'ah prayer or the last unit of the Maghrib prayer, when done out of forgetfulness. There are two narrations regarding legislating prostration of forgetfulness for this omission. One view states that prostration is not legislated because the prayer is not invalidated by the intentional act, just as with omitting recommended actions (*sunan al-af'al*). The second view states that prostration is legislated, based on the Prophet's saying: If one of you forgets, let him prostrate two prostrations while sitting (Reported by Muslim). If prostration is legislated, it is recommended (*mustahabb*) and not obligatory, as it compensates for a non-obligatory act, similar to compensating for other recommended sunnahs. Ahmad stated that the only forgetfulness requiring prostration is what is narrated from the Prophet, and the default ruling is the non-obligation of prostration.