Rejection of insurance claim - reg.

ICICI Lombard rejected my claim for theft of two wheeler on the ground of delay in reporting the theft. My bike was stolen on 22/09/2019 whereas, I cam to know about it only on 24/09/2019 when I found it missing from my dedicated parking slot. Within 48 hours lodged the FIR and intimated the same to the insurance company the next day. I had also submitted a grievance with the IRDA on this issue however, to no avail. Do I have a remedy to secure the insurance claim.