Is it obligatory to recite a surah after Al-Fatiha in prayer according to the Hanafis, and if the worshiper forgets it and bows, should he go back to recite it or perform the prostration of forgetfulness (sujud al-sahw)?

Reciting a Sura after Al-Fatiha in the Fajr prayer and in the first two rak'ahs of the other five prayers is obligatory according to the Hanafis. If one misses it out of forgetfulness, the prostration of forgetfulness (sujud sahwi) becomes necessary. The missed recitation is to be made up by returning to it before prostrating. If the worshipper remembers it during the bowing (ruku') or after rising from it, he returns to recite it, then repeats the bowing, and performs the prostration of forgetfulness. As for the majority of scholars, they hold that reciting the Sura is a recommended sunnah and its place is while standing (qiyam). It is missed if its place is missed, and one performs the prostration of forgetfulness for omitting it out of forgetfulness.