Hi,

So I encountered this weird bug today, a couple of days after updating my Realms world from 1.13.2, and it only effect a certain area. My base.

Everything was normal at first, but all of a sudden the light sources at my underground base stopped emiting light. Turning the whole area dark, and I get mob spawns everywhere. 

I use different light sources (torches, glowstone, end rods), and the bug effects all of them. If I update the block next to the light source it starts to emit light again, but as soon as I leave the area and come back, I have the same problem.

It seems to only effect the areas that are completely underground, and not areas that get skylight. So far this problem has only occurred at my base.

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Maybe it`s the latest version of Java? I think it happened after I updated. 
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