[2020] Is anyone else having issues recently getting enemies to spawn in blast zones while in a private world?

I've done 5 blast zones in a private world in the past two days. No enemies spawn. Even the old trick of leaving the world and coming back in doesn't trigger them to spawn. I do blast zones jn a private world all the time and leaving the world and coming back in has always worked before.

Anyone else know any other tricks? Has anyone else had issues recently?