Fatwa No : 445414
She Doubts About Pronouncing Some Letters of Al-Faatihah Incorrectly
Fatwa Date : Thul-Hijjah 26, 1442 / 4-8-2021
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
What appears from the question is that you are afflicted with whispers and doubts; therefore, we advise you to avoid them and not pay any attention to them, for this is the beneficial treatment for them.
With regard to the doubts that you have about pronouncing any letter from Al-Fatihah correctly, or adding a letter, and whether this happened by mistake or not, then all of this stems from whispers, so just ignore them and do not pay attention to them. You should recite in a natural manner, and your prayer is valid, and it is not invalidated by mere doubt. In principle, the prayer is valid and it is not invalidated except with certainty.
Allah knows best.