“Your options may be few at this point.
If your insurance company has not already issued a formal written denial of coverage, ask them to do so. The rental company would much rather make a claim against your insurance than pursue you directly, so you may be able to ask their claims department for help in dealing with your insurance company.
If you have any credit cards, review your terms to see if you might have any coverage there. Some credit card companies provide collision coverage
for a rental car, but they might have needed to be notified of the rental ahead of time. If you foresee that you will be unable to pay for the damage to the rental car, and if you have no other coverage, you will want to consult with a legal professional who can review the insurance policy and rental car contracts. They would advise you further on what options you have.
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