According to IRDAI regulations, a death claim under a life insurance policy must be paid, denied, or rejected with all necessary justifications within 30 days on the day that all necessary paperwork and explanations were received. However, if the insurer determines that the circumstances of a claim necessitate an investigation, it must begin as soon as possible, finish the investigation quickly, and do so no later than 90 days after the insurer receives notice of the claim. The claim must then be resolved within 30 days after the insurer's completion of the investigation.
Source: https://www.irdai.gov.in/ADMINCMS/cms/Uploadedfiles/RTI_FAQ/RTI_Dept.pdf