I gave myself EVERY recipe to myself with the /recipe give @s * command, and there was nothing in the recipe book in a Furnace or a Crafting Table about the Dried Kelp Block. I even looked up the block id thing of the Dried Kelp Block, and did the command to give myself only that recipe (/recipe give @s minecraft:dried_kelp_block). When I did it gave me an error "Unknown recipe: minecraft:dried_kelp_block".