I keep getting a bug where chunks of the world get a dark shadow like there is no light source nearby and in some instances its in blocks adjacent to the light source. As soon as I put a light source in the shadowed area, it lights up, again and I can break the light source I put down and the original intended light source in that area keeps it lit up.
Thank you for your report!
We're actually already tracking this issue under MCPE-58182 so I've requested this report be resolved and linked as a duplicate.
That ticket has already been resolved as Fixed which means the fix will arrive in the next version or is already included in the latest development version of the game. You can check the Fix Version/s field in that ticket to learn more.
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