Colossus Fight - Titan Grotto - Impervious to Damage

As the title suggests, I somehow force the Colossus to bug during the boss fight after I have broken its armor and used totems.

I am playing Warrior, using the Smith of Kitava ascendancy and I have the Living weapon skill. Both times I have gotten this bug, I broke armor and used totems. I have had this happen twice and am about to go for take 3.

Take 3 died. Take 4 same bug. Going to see how long he stays this way to test a bit more.

Take 5 I was able to finish it no bugs. I Changed nothing about how I did the fight.

Just in case anyone is having this issue, I had the same problem playing shockwave totem warbringer, and i managed to "unbug" the colossus by using infernal cry with corrupting cry, It seemed to let him phase correctly since he would be taking some damage.

Also had this issue, also using shockwave totems!

https://www.twitch.tv/sjatar_/clip/GentleInnocentCrabsTwitchRPG-K6UHUQ1vk9ZxLe_M

Also had this issue, with both ranged, curse, melee and minion attacks. Whenever he stood on the right side after 2 pieces of floor had broken off he would be completely untargetable.