You can appeal the decision of the insurance company to reject your claim. Read your insurance policy thoroughly and check if the reason why your request got denied. If you feel like the reason for the rejection is invalid, write your insurance company and state their mistake. Provide evidence and documentation as to why your insurance claim should not have been rejected.
For more details about this, you may visit https://www.hoganinjury.com/denied-auto-insurance-claim-what-do-i-do/