The Dink Network

I've spent quite some time levelling up so I can take on the hags. I succeeded in that I can beat them. However, when I kill any two (doesn't matter which), the last one will freeze and it's impossible to hit it any further. I won't die as long as I don't touch it, but I can't kill it either, and there's a screen lock. Looks like a bug to me. Am I not supposed to be able to beat them? In that case I have no idea what else I could still do...