Infrastructure Development Finance Company [IDFC] — payment not received till now

Dear sir,
I have purchased four number of bonds with a face value of rs.5000/- each for which i give below the details.
Series: z 119998 isin : ine043d07781
Registered folio no.: idd0284271 certificate no. 284271
Name of bond holder : k ramachandran
No. Of bonds : four only
Distinctive no (S).: [protected] - [protected]
Buyback date : december 31, 2016
Amount payable on buyback per bond rs.7695
Date : december 30, 2011
Now it is more than two and half years elapsed since 31/12/2016 (Buyback date) as mentioned in the certificate. Till date i have neither received a fresh bond nor the maturity amount has been credited to my account.
Please look into the matter and do the needful at the earliest to safeguard the interest of the depositors.
Thanking you,
Yours faithfully,

K ramachandran

Date 11 07 2019