This can be seen in CanPlaceOn and CanDestroy tags.
/give @s stone{CanPlaceOn:["kelp","tall_sea_grass","bubble_column"]}This can be fixed by adding the following to the lang file:
"block.minecraft.kelp": "Kelp",
"block.minecraft.tall_sea_grass": "Tall Sea Grass",
"block.minecraft.bubble_column": "Bubble Column",This would cause kelp and kelp_top to share the same string value, in order to fix that, change "block.minecraft.kelp_top": "Kelp" to "block.minecraft.kelp_top": "Kelp Top" this will result in the item name changing though, changing the item id to kelp would fix that in turn.
Screenshot of bugged Coral Plant names: