LFG paid my brother's claim in 2013, but they are refusing now – for the same condition

My brother has been disabled twice for the same mental illness. The first time Lincoln Financial paid his claim without any problems (2013). This time he was disabled at his job for the same mental illness and he was denied. We appealed it and was denied again. I filed a complaint on his behalf with the Department of Insurance for the State of California. They still stand that they are denying short term disability for my brother. We have a chance to file a final appeal by 3/2016. It is frustrating how difficult they are being as opposed to the last time where they just sent a check after my father and I helped fill out all the paperwork on my brother’s behalf because he was in the hospital. I plan to file the final appeal on my brother’s behalf and if that doesn’t work I will go back to the Department of Insurance and ask for a independent medical review.