You issue a legal notice to the branch manager under whose jurisdiction your father served as an agent, with a copy to the marketing manager of the division office nd the senior division manager, with a copy to the Zonal manager.
You have to give the details of policy numbers for which your father was eligible for hereditary renewal commissions .
If you do not get any reply within the time stipulated in the legal notice, you may file a suit for mandatory injunction against the above said officials seeking direction to settle the claims of HRC as claimed by you, which would be arrears or future commissions in your favor.
If you were a nominee then the commission amount will have to be settled to your name as and when one arises.
If you do not want to file injunction suit, you can opt to approach consumer forum for deficiency in service or high court with a writ petition seeking relief and remedy