Server crash

[EmporiumDevelopment]

[Server thread/CRITICAL]: InvalidArgumentException: "Entity Library\EntityAPI\entity\types\NPC is not registered" (EXCEPTION) in "pmsrc/src/entity/EntityFactory" at line 243
--- Stack trace ---
#0 pmsrc/src/entity/Entity(485): pocketmine\entity\EntityFactory->injectSaveId(string[34] Library\EntityAPI\entity\types\NPC, object pocketmine\nbt\tag\CompoundTag#177382)
#1 pmsrc/src/entity/Living(274): pocketmine\entity\Entity->saveNBT()
#2 pmsrc/src/entity/Human(398): pocketmine\entity\Living->saveNBT()
#3 plugins/Emporium-Core/src/Library/EntityAPI/entity/types/NPC(29): pocketmine\entity\Human->saveNBT()
#4 pmsrc/src/world/World(2739): Library\EntityAPI\entity\types\NPC->saveNBT()
#5 (): pocketmine\world\World->pocketmine\world{closure}(object Library\EntityAPI\entity\types\NPC#173218)
#6 pmsrc/src/world/World(2739): array_map(object Closure#176935, array[2])
#7 pmsrc/src/world/World(605): pocketmine\world\World->unloadChunk(int 16, int 13, false)
#8 pmsrc/src/world/WorldManager(162): pocketmine\world\World->onUnload()
#9 pmsrc/src/Server(1495): pocketmine\world\WorldManager->unloadWorld(object pocketmine\world\World#26418, true)
#10 pmsrc/src/Server(1672): pocketmine\Server->forceShutdown()
#11 pmsrc/src/Server(1569): pocketmine\Server->crashDump()
#12 pmsrc/src/Server(1064): pocketmine\Server->exceptionHandler(object InvalidArgumentException#179279)
#13 pmsrc/src/PocketMine(328): pocketmine\Server->__construct(object BaseClassLoader#4, object pocketmine\utils\MainLogger#3, string[41] C:\Users\brant\Desktop\Emporium SkyBlock, string[49] C:\Users\brant\Desktop\Emporium SkyBlock\plugins)
#14 pmsrc/src/PocketMine(351): pocketmine\server()
#15 pmsrc(11): require(string[85] phar://C:/Users/brant/Desktop/Emporium SkyBlock/PocketMine-MP.phar/src/PocketMin)
--- End of exception information ---

i get this crash a few minutes after i create an entity pm4 4.12.0

[JonyGamesYT9]

Not is a library, add the plugin in your server.