Every Insurance company has internal grievance redressal mechanism for redressal of complaints by Consumers. Any consumer before filing a complaint against Insurance Company must approach internal grievance machinery of Insurance Company. They have internal escalation matrix to solve the complaint.
If the consumer is not satisfied with their response they can approach either Insurance Ombudsman or IGMS https://igms.irda.gov.in
Here are links to the Grievance Redressal Policies of all the Life insurance Companies and Non-Life Insurance Companies