RA 9255 how can i fix my surname if my father cant help me anymore thanks!!!!

Hi i just recntly found out na nkregister po sa Nso as my surname is my mom's surname and ive been using my dad's surname ever since. I know i need to get ausf and admission of paternity/ acknowledge. My question po is I cant bring my father in LCR Manila where I was born coz he's too old pra mgbyahe byahe pa. Is it possible po ba dto na ako kumuha sa pampanga ng admission of paternity/acknowledgement and then i file ko nlang sa LCR manila? They told me po kc sa notary public dto na I need to know muna po if ttangapin ung affdvit from here. Kc dw po minsan mselan ung mga LCRO kung san ka pngnak dun dw dpat kunin ung affdvit of paternity. Any idea po? Thank you ng marmi!

Anyway im 22 yrs old po. And wala po nkaattach na affdvit of paternity dun sa COLB ko. If hindi ko po pwede kunin ung affdavit here sa pampanga, ano po iba option na pde ko gwin not involving my father personal appearance? He can do private handwritten and we can submit proofs namn po it is just that nde na mkabyahe. Hindi ko po alam step to step process and I really need someone to enlighten me. Thanks po!!!