By mistake he said when bowing, “Subhaana rabbiy al-a‘la”

Sometimes during the prayer on the rukoo instead od saying "subhanRabi
azim " i say "subhan Rabi 'ala " , but i notice it before finishing
the saying or sometimes afterthe saying and i corect , the same happen
to me during the sujood i say the opposite and also between the two
prostrations ? do i have todo the prostrations of forgetfulness ? if
yes after or before?.
Praise be to Allaah.
Firstly:
If a person forgets and says when bowing "Subhaana rabbiy al-a'la" by
mistake, or he says when prostrating, "Subhaana rabbiy al-'azeem", it
is one of two scenarios:
(i) He remembersthat he did not say the dhikr in the
right place, in which case he should say "Subhaan rabbiy al-'azeem"
before rising from bowing, and he should say when prostrating
"Subhaana rabbiy al-a'la" before he sits up.
In this case he does not have to do the prostrationof forgetfulness,
because he did not omit something that is obligatory; rather it is
mustahabb for him to do the prostration of forgetfulness, because he
did not say the dhikr in the right place.
(ii) He does not remember that he did notsay the dhikr in
the right place until after rising from bowing or prostration.
In this case he has to do the prostration of forgetfulness because he
omitted something obligatory.
In this case the prostration should come before the salaam.
We have previously discussed this issue in the answer to question no. 7743
Shaykh Ibn 'Uthaymeen (may Allah have mercy onhim) said: If a person
says a prescribed phrase in the wrong place, it is prescribed for him
to do the prostration of forgetfulness, such as if hesays "Subhaana
rabbiy al-a'la" whilst bowing, then he remembers and says "Subhaana
rabbiy al-'azeem" In this case, he said a phrase that is prescribed,
namely "Subhaana rabbiy al-a'la", but it is prescribed to say
"Subhaana rabbiy al-a'la" when prostrating. So if he says it when
bowing, we say: You said something that is prescribed in the wrong
place, so doing theprostration (of forgetfulness) is Sunnah inyour
case.
End quote from ash-Sharhal-Mumti', 3/359
Shaykh Ibn Jibreen (may Allah have mercy on him) said: If he says a
prescribed phrase in the wrong place by mistake, itdoes not invalidate
the prayer… so if he recites Qur'aan when he is sittingor recites the
Tashahhud when he is standing, or hesays "Subhaana rabbiy al-a'la"
whilst bowing or "Subhaana rabbiy al-'azeem" whilst prostrating, i.e.,
he does something that is Sunnah in the wrong place even though it is
prescribed, then it is Sunnah for him to do the prostration of
forgetfulness, but it is not obligatory, because these phrases all
come under the heading of adhkaar al-salaat (dhikrs recited during the
prayer), so the prayer is not invalidated by doing so. End quote from
Sharh Akhdar al-Mukhtasaraat
Secondly:
If the worshipper was praying behind an imam and did any of the things
mentioned above, then heshould do the prostration of forgetfulness at
the end of his prayer, if he joined the prayer late. If he offered the
entire prayer from the beginning with the imam,then he should say the
salaam with the imam and he does not have to do the prostration of
forgetfulness.
Shaykh Ibn 'Uthaymeen (may Allah have mercy onhim) said: If one who is
praying behind an imam makes a mistake in his prayer, and he did not
join the prayer late, i.e., hedid all the rak'ahs with the imam, such
as if he forgot to say "Subhaana rabbiy al-'azeem" when bowing, he
does not haveto do the prostration of forgetfulness, because theimam
has borne it for him. But if we assume that the one who prayed behind
the imam made a mistake that caused one of the rak'ahs to be
invalidated, such as if he forgot to recite al-Faatihah, then in this
case, when the imam saysthe salaam, he has to stand up and do the
rak'ah that was invalidated because of his mistake, then he should
recite the tashahhud, say the salaam and do the prostration of
forgetfulness after the salaam.
But if the one who prays behind the imam makes amistake in his prayer
and he joined the prayer late, then he should do the prostration of
forgetfulness, whether hismistake came when he was praying with the
imam or after he stood upto complete what he had missed, because if he
prostrates he will not be going against his imam, because his imam
will have already finished his prayer.

And Allah knows best.