Is it obligatory to repeat the prayers of past years due to water not reaching the circumcision area and the navel during ghusl janaba (ritual bath after sexual impurity) because of ignorance, and is this excusable based on the hadith: "Lifted from my Ummah (community) are mistakes, forgetfulness, and what they are compelled to do"?

If a Muslim covers his entire body with water during ghusl, and the water reaches all concealed areas of the body that have the ruling of being apparent, such as the inside of the navel, the groins, and the armpits, then his ghusl is valid. However, if the water does not reach these areas, then the purification is incomplete, and he must repeat the prayers he performed in an incorrect state. If he does not know their number, he must strive to clear his conscience. As for the penis, if water does not reach it except by moving what covers it, then ghusl is not complete unless water reaches all apparent parts of the body, and the rulings concerning prayers performed with incomplete purification apply to it. Ignorance is not an excuse for failing to purify from ritual impurity. However, Shaykh al-Islam Ibn Taymiyyah is of the view that whoever omits something due to ignorance of its ruling is not obliged to repeat what has passed, but rather must adhere to it in the future.