What must I do concerning the prayers that I performed for three years without ritual bathing (ghusl) from major impurity (janabah), due to ignorance of its obligation?

Ghusl is obligatory if a Muslim wakes up and finds semen on his clothes or body, even if he does not recall a wet dream, because the emission of semen necessitates Ghusl. However, if he had a wet dream but nothing was emitted, Ghusl is not obligatory. One who neglected Ghusl for three years out of ignorance must consult scholars, because ignorance is not an excuse. He must fear Allah and perform many supererogatory acts of worship. Some scholars obligate making up the prayers, while others believe that one should perform many supererogatory acts if the matter was due to ignorance and for a long period.