What is the ruling on forgetting some verses of the Qur’an during an individual prayer?

If a worshiper, whether praying alone or as an imam, inadvertently omits verses from the Qur'an in their prayer:

- If the forgotten verses are from other than Al-Fatihah, nothing is entailed.

- However, if they are from Al-Fatihah:

- If the worshiper remembers them before bowing (ruku'), they should recite them, and no prostration of forgetfulness (sujood as-sahw) is required.

- If they remember them after completing the bowing, the rak'ah in which Al-Fatihah was not recited completely becomes void, and the subsequent rak'ah takes its place.

- If the worshiper does not realize the omission until after the salutation (taslim), they should perform a rak'ah in place of the omitted one if they remember it shortly thereafter. Otherwise, their prayer is invalidated, because Al-Fatihah is an essential pillar (rukn) in every rak'ah, based on the Prophet's (peace be upon him) saying: "There is no prayer for one who does not recite the Opening of the Book (Al-Fatihah)."