ONGC — Non payment of my epf amount even after 21 years

I joined ongc on 7th feb 1983 and resigned ion 1st. October 1996. From sibsagar, assam though i filled the claim form for my cpf claim, i did not get any response. That time i was serving outside india. I came to india in 2007 & againi submitted cpf claim forms to p & a assam again but still got no response. My then cpf no. Was 50170
Its almost 21 years i have resigned & still not got my cpf back.
Will i get my hard eaned money back? If so how?

Regards,
Sanjay kumar sood
Cpf no. 50170
Resigned as dy. Suptdg. Chemist