What is the ruling on someone who interrupted the prostration of forgetfulness (sujud al-sahw) after finishing the prayer, then repeated it due to a doubt that occurred to him while saying the takbir for it, and does his prayer become invalidated by that?

If a worshiper doubts the takbir for the prostration of forgetfulness ( sujud al-sahw) and stands up to repeat it:

- If sujud al-sahw is performed after the prayer, there is no issue, but his action is incorrect because he has already exited the prayer. - If sujud al-sahw is performed before the prayer, he has erred because the takbirat of transition are obligatory. Intentionally omitting them invalidates the prayer, but omitting them out of forgetfulness or ignorance does not invalidate it and requires sujud al-sahw. Forgetfulness during sujud al-sahw does not necessitate repeating it, and no attention should be paid to doubt about omitting the takbir. - Once one begins prostrating, it is impermissible to return to an omitted or doubted obligatory act. - The prayer is valid and does not need to be repeated if his action was due to ignorance of the ruling.