What is the ruling on the prayer of one who performed ablution by presenting one limb before another for five years out of ignorance, and is it obligatory to repeat the prayers of these years?

Scholars have differed regarding the ruling on the order of ablution (wudu'). Ahmad and Al-Shafi'i held that it is obligatory, while the Malikis, Hanafis, and Ahmad in one narration from him, held that it is a Sunnah and not obligatory. Accordingly, the prayer of one who reversed the order of his ablution (putting forward what should be delayed or delaying what should be put forward) is considered valid by the Hanafis, Malikis, and in one narration from Ahmad. There is no harm in adopting this view concerning past prayers, but the order must be observed in the future. However, according to the view that sequencing is obligatory (the madhhab of the Shafi'is and Hanbalis), the missed prayers must be redone. This latter view is more cautious if it can be done without great difficulty. It is incumbent upon a mukallaf (accountable person) to learn what rectifies his faith and worship, such as the rulings of purification and prayer.