Reciting Fatihah in attahiyyaat

Question: If one read Surah Fatiha in tashahhud, thereafter remembered his error and read tashahhud, does he have to make sajday sahw?

Answer:

No, the expalnation to this is as follows: If he read Fatihah in place of tashahhud or read Surah Fatiha then tashahhud, he must make sajdah sahw.

If he first read tashahhud then Fatihah, there is no sajdah sahw on him.