Blight Monster Portal Spawn ontop of Starfall Crater - Stops minions spawning

Completed the Starfall Crater boss - Pit of Chimera

Come out, triggered the blight, killed all mobs.

But then could see a red glow of mobs on the mini map with remaining mobs (can just about see it on right of screenshot under my character).

image shows a spider stuck in the portal ontop of the crater.

mob cannot be targetted by me or towers (tried meteor tower)



image not working, heres link
https://imgur.com/a/gx6TrQ6