Exploit around a recipe I created regarding respawn anchors anchors.

For my SMP the datapack I created meant to nerf crystal pvp while still making it available in short bursts. So I made the recipe for the respawn anchor and crystal yield the item that can only stack up to 16 for crystals and up to 8 on anchors, however when it comes to the anchors, it is possible to just place and pick back up the anchor for it to stack to 64 again. Any way to fix this exploit?