Based on adiyen’s understanding – after one who has undergone prapatti at an young age, commits several intentional and unintentional sinful deeds. The unintentional sins are ignored but for intentional sinful deeds only when one performs prayschitta (atonement) prapatti, there will not be any obstacles for attaining moksham. Is adiyen’s understanding correct? What will happen when one does not perform prayschitta prapatti?

One’s attainment of moksham will not be prevented when one commits intentional sinful deeds after having undergone prapatti at a young age. Performance of prapatti will certainly lead one to moksham.
However, there are two dangers – association with demi-gods and offending a bhagavata. These two must be avoided, and all other types of sins will not impact prapatti.
For all other sinful deeds whether done deliberately or unwittingly, Emperuman will punish lightly. After the completion of such punishments, prapatti will certainly yield fruits. If one does not want to undergo the lighter punishments, they can do prayaschitta prapatti as atonement to remove obstacles to attaining moksham. It is not mandatory to perform prayaschitta prapatti; even when does not do so, moksham will ensue because of prapatti.