Park brake stuck on 85 xt

I have an 85XT that wont move. All 3 of the safety lights are illuminated. The 10 amp fuse and the relay checks out but the brake wont release. A few days ago I broke a line on my tree sheer and lost some fluid, not sure how much so I added a gallon of oil. Sight glass is very hard for me to see what the level is but I didn't think I lost more than that. However after about 3 hours of use the parking brake slightly engaged a few times and then just locked up and wont release. HELP Please.

Park brake stuck on 85 xt