Lightning warp unable to cast in Zahmir boss fight

Abyss spawned deep in Zahmir t15 map boss arena, had to bait each abyssal enemy out of boss room to kill. Finally cleared them all, went to fight boss and my lightning warp would spend mana but not cast or deal damage. I tried placing it on a different keybinding, but it was still unable to deal damage.

Image once I died:
https://gyazo.com/7628cdc1175ee08c7f47bb6c9f5951a4

I ran into the same exact bug a second time on T16 map. Zahmir arena with an abyss inside, using ball lightning for lightning warp. The missing cull target sound plays, and mana is spent, but no lightning warp casts. I walked outside the boss arena and can lightning warp completely normally. Tried multiple slots, tried removing and adding back gear, nothing changed. It seemed to be just in the arena.

Clip example captured below:
https://youtu.be/Wv5HEgLb_Do