Postal life insurance maturity value

Sir, Insurant of Postal Life Insurant expired before receipt of maturity value. Sanction for payment of maturity value of PLI policy was already issued, but insurant was hospitalized and was unable to surrender sanction copy and was unable to get payment from Department of Posts. How it will be treated ? Is is death claim to be preferred by legal heir or by nominee of the policy ? How and modalities please ?