Jade Isle Boss bugged

This is the second time this happened to me and its quite annoying at this point especially since the boss can drop a valuable item.

The first time, the boss transformed but didnt move to the 2nd arena. i was also softlocked after the forced knockdown. I have tried Ctrl + login to character and it just remove 1 portal but the boss still stucked. I was able to access the 2nd arena but nothings really happening

https://streamable.com/l6v06x

Second time, different character. The boss didnt even transformed it just stayed on the first phase

https://streamable.com/fntgg7