Discovery Insure refuses to pay for legitimate claim

I registered a claim with Discovery Insure to fix damages to my front bumper which got damaged as a result of getting caught on the pavement. When this happened there was pressure on the join that connects the fender and the bumper which resulted in a crack on the fender. Discovery refuses to pay for the fender damage, only stating that it is old damage but failing to provide details of how their assessor came to the conclusion. To make matters worse, no-one at Discovery bothered to inform me of this refusal, I found this out via the panel beater when I followed up on repair progress. This is so pathetic, I have cancelled my policy and will take this to the Insurance Ombudsman