Not Showing Items

[Zoolokay]

When I load in on Minecraft, or even after playing for a while, the barrels will not show what item is placed inside them. I can left-click to get the item out and right-click to put the same item inside. I can also destroy the barrel and in my inventory it will say what item is inside of it, but even after placing it back down again, it will not display the item.

I have obsidian shells on my barrels and only shows items for maybe 8 barrels in another location on the world.