IFCI — Regarding Redeeming of IFCI Long Term Infrastructure Bonds Series II

D/A,

My father has purchased 4 IFCI Long Term Infrastructure Bonds Series II on 8th March 2011, These bonds has now matured on 31st Jan 2021 and we have not yet received the maturity amount including interest in the bank account who's details where mentioned on bond issuance letter.
Hence I would like to know the process through which I could redeem my maturity amount including interest. The bond details are mentioned below for reference:
No of Bonds- 4
Amount- 20, 000
Folio No- 2085032
Certificate No- 2045054

Regards
Gaurav Sharma
Contact- [protected]
Email- [protected]@gmail.com