Jet Airways — non receipt of ticket refund wrt cancelled flight march 18

Pnr; owqrqg ticket nos;[protected] and 6218
Singapore - delhi flight 9w 19
Passengers; ajay aggarwal and [censored]al aggarwal
Above flight of march 18, 2018 was cancelled by jetair vide their email on march 6, 2019. I contacted call centre on 15/03 to confirm cancellation. Was promised refund within a week. Only half refund rs. 39, 893.00 received to date.

Why is the balance not being refunded despite reminmders.