Boss Shop and MMOItems

[16:16:22] [Server thread/INFO]: [MMOItems] Hooked onto Vault
[16:16:22] [Server thread/INFO]: [MMOItems] Loading crafting stations, please wait..
[16:16:22] [Server thread/INFO]: [MMOItems] Hooked onto RPGInventory
[16:16:22] [Server thread/INFO]: [MMOItems] Hooked onto HolographicDisplays
[16:16:22] [Server thread/INFO]: [MMOItems] Hooked onto PlaceholderAPI
[16:16:22] [Server thread/INFO]: [PlaceholderAPI] Successfully registered expansion: mmoitems
[16:16:22] [Server thread/INFO]: [MMOItems] Hooked onto GlowAPI (Item Glow)
[16:16:22] [Server thread/ERROR]: Error occurred while enabling MMOItems v6.2.4 (Is it up to date?)
java.lang.NullPointerException: null
    at org.black_ixx.bossshop.core.rewards.BSRewardType.registerType(BSRewardType.java:60) ~[?:?]
    at org.black_ixx.bossshop.core.rewards.BSRewardType.register(BSRewardType.java:91) ~[?:?]
    at net.Indyuce.mmoitems.MMOItems.onEnable(MMOItems.java:288) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:263) ~[patched_1.16.3.jar:git-Paper-249]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:380) ~[patched_1.16.3.jar:git-Paper-249]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:483) ~[patched_1.16.3.jar:git-Paper-249]
    at org.bukkit.craftbukkit.v1_16_R2.CraftServer.enablePlugin(CraftServer.java:501) ~[patched_1.16.3.jar:git-Paper-249]
    at org.bukkit.craftbukkit.v1_16_R2.CraftServer.enablePlugins(CraftServer.java:415) ~[patched_1.16.3.jar:git-Paper-249]
    at net.minecraft.server.v1_16_R2.MinecraftServer.loadWorld(MinecraftServer.java:468) ~[patched_1.16.3.jar:git-Paper-249]
    at net.minecraft.server.v1_16_R2.DedicatedServer.init(DedicatedServer.java:237) ~[patched_1.16.3.jar:git-Paper-249]
    at net.minecraft.server.v1_16_R2.MinecraftServer.w(MinecraftServer.java:939) ~[patched_1.16.3.jar:git-Paper-249]
    at net.minecraft.server.v1_16_R2.MinecraftServer.lambda$a$0(MinecraftServer.java:177) ~[patched_1.16.3.jar:git-Paper-249]
    at java.lang.Thread.run(Thread.java:834) [?:?]
[16:16:22] [Server thread/INFO]: [MMOItems] Disabling MMOItems v6.2.4
[16:16:22] [Server thread/INFO]: [RPGChest] Enabling RPGChest v3.1.0