SSS and my married surname

I have a problem now with how I could have my marriage annulled so I could have one of my SSS numbers deleted and have my single name used in all my SSS transactions. Dalawa kasi ang naging SSS number ko – one with my married surname (which was lost for God knows when), and one with my maiden surname (which i got not knowing the future implications of such)
Mahigit 24 years napo kaming hiwalay ng aking asawa at wala na kaming kahit na anong komunikasyon sa loob ng mga panahong iyon. At mahigit 20 years ko na rin hindi ginagamit ang kanyang apelyido. Yung maiden name ko po ang ginagamit ko. Sa panahong iyon, ako po ay nagkaanak sa ibang lalaki pero hindi namn po kami nagsama at matagal na rin kaming hiwalay.
Mahal alam ko ang annulment fees, but is there a legal process that could have my marriage declared void on the ground that after more than 24 years without seeing my husband and without communication or knowledge as to his whereabouts, i could pronounce him as dead? So I can have one of my SSS numbers deleted and for my surname be reverted back to my maiden name? Please advise
Also, how much is the annulment fee, if i may ask? If in case i do not have enough resources to pursue this, what can be my resort? Thank you and God bless

not uncommon to hear legal fees and costs at 150-300k