Is it obligatory to repeat the middle Tashahhud if a worshiper doubts whether he performed the second prostration, and then it becomes clear to him that he did perform it?

If a person suffering from obsessive doubts (al-muswas) doubts whether he omitted the second prostration, he should disregard his doubt. As for a person who does not suffer from obsessive doubts, if he doubts whether he omitted the second prostration, he should perform it, and then perform the prostrations of forgetfulness (sujud al-sahw) after the salutations of peace. He does not need to repeat the Tashahhud if it becomes clear that his first prostration was valid; rather, he should immediately stand up for the third rak'ah. If he intentionally repeats it, his prayer becomes void because he intentionally added an extra sitting. However, if he repeats it out of ignorance, his prayer is not void, and he should perform the prostrations of forgetfulness.