It's Been some time now and this issue is still around! Usually It doesn't matter because you can still end up winning the boss fight, but now I am stuck on my final boss because its not just glitchin its actually restoring and saving the health! Contact Zynga Support if you are having the issue, if they don't get complaints about it they wont do anything!
Normally this happens..
But recently its actually saving the health its restoring and even though I have inflicted 100,000+ damage my final boss is still alive with over 75% of his health!! And it's been like this every single time I try to fight the final boss!!