What is the ruling on frequent doubt in prayer, especially when doubting the omission of a pillar or a duty, and is it permissible to interrupt the prayer and repeat what was doubted, or is it obligatory to complete the prayer and then perform the prostration of forgetfulness, and what about someone who is not at ease with ignoring these whispers and feels that their prayer is incomplete?

Whoever forgets a pillar in a rak'ah (unit of prayer) and has not reached its place in the subsequent rak'ah, should return to it. Otherwise, they should perform a rak'ah in its stead. However, returning to the first tashahhud (definition) after standing up and completing the standing is not of this category because it is not a pillar, and scholars have differed concerning it. It appears that the questioner is afflicted with waswasah (obsessive whispering), and its only cure is to disregard it and continue with the prayer without paying attention to doubts. No prostration of forgetfulness (sujud (definition) al-sahw) is required of her. Abandoning waswasah brings ease in both religious and worldly matters, while giving in to it may lead to sin.