Zalmarath the Colossus falling under the map bug

Been trying to beat Zalmarath the Colossus and it is making the boss fight more artificially difficult the fact that every few moments I am launched either into the stratosphere or launched under the map and then reset during an attack or frozen solid with the mobs freezing me and disintegrating my health.

I know he is not a difficult boss it is just this bug that makes it harder than it has to be.

I do not know how this bug happens and how to recreate it consistently but it is a frequent occurrence within the fight.

Here is a link for a visual representation of what happens:

https://youtu.be/OEHz6Dm0TKU