Discovery Life Capital Disability Claim Denied

Been diagnosed with Rheumatoid arthritis and Discovery has denied my claim for capital disability benefits even though I have been unable to work for the past 8 months. I took my policy out over 10 years ago in order to protect me from such an event. The independent OT report shows the amount of strain I am under and unable to conduct my duties in the construction industry but still the claim is denied, I feel like I’ve been paying for this “protection” for nothing.