What is the ruling if the substitute repeats the prayer from the beginning?
Machine translationRead the Arabic original
Question:
If the imam appointed a substitute and had already prayed two rak'ahs, but this substitute did not know the ruling and started over from the beginning?
Answer:
It does no harm; his prayer is valid. If he started over from the beginning, there is nothing wrong with it, but the recommended practice is to complete the prayer just as 'Abd al-Rahman completed it with them.
If the imam appointed a substitute and had already prayed two rak'ahs, but this substitute did not know the ruling and started over from the beginning?
Answer:
It does no harm; his prayer is valid. If he started over from the beginning, there is nothing wrong with it, but the recommended practice is to complete the prayer just as 'Abd al-Rahman completed it with them.
Source
binbaz.org.sa
The Arabic text is copied verbatim from the original source, without any edits.