NEED HELP!!!!!

NEED HELP....I've been using my last name YAMAJI since nag start ak mag aral and magtrabaho for some part time jobs during my college years only to find out later on na YAMAGI pala ung nasa birth certificate ko. So to make it easier inadopt ko na ung last name reflected s birth ko which is YAMAGI nga. With plans going abroad kumuha ak ng passport last year and was denied cos of having several incorrect entries sa birth. First, my mom is a Filipino and my Father is a japanese, his whereabouts ndi ko po alam, but dun s birth ko s entry nung s mom ko nakalagay na JAPANESE din xa and religion is buddhism. nakalagay dn n married cla, there's even a date indicated and place of marriage,but wala naman pong signature s father side.

Mas ok po ba na mag pa late register na lang ako using YAMAJI? Nagconsult po ak sa isang lawyer via PAO but got not much info // ang sabi lng eh correction of entry daw po and malaki gagastusin ko... wour advice would be very much appreciated.. god bless