Ring suddenly fallen

I was farming a map clearing breaches in my last portal, and completely out of nowhere my ring dropped without me dragging it out of my inventory I didn't even open my inventory. When I lost my stat of dex, my build broke, and I couldn't attack, so I just died to the mobs in the lanes...
I don't know if this has happened to anyone else, but I'm not sending this to get the item back..I'm just reporting the bug.