error

[20:24:57 INFO]: [PlaceholderAPI] Placeholder expansion registration initializing...
[20:24:57 ERROR]: Could not pass event ServerLoadEvent to PlaceholderAPI v2.10.4
java.lang.NoClassDefFoundError: net/luckperms/api/LuckPerms
        at me.lucko.luckperms.placeholders.LuckPermsExpansion.canRegister(LuckPermsExpansion.java:48) ~[?:?]
        at me.clip.placeholderapi.expansion.ExpansionManager.registerExpansion(ExpansionManager.java:102) ~[?:?]
        at me.clip.placeholderapi.expansion.ExpansionManager.registerAllExpansions(ExpansionManager.java:154) ~[?:?]
        at me.clip.placeholderapi.ServerLoadEventListener.onServerLoad(ServerLoadEventListener.java:52) ~[?:?]
        at com.destroystokyo.paper.event.executor.asm.generated.GeneratedEventExecutor33.execute(Unknown Source) ~[?:?]
        at org.bukkit.plugin.EventExecutor.lambda$create$1(EventExecutor.java:69) ~[patched_1.14.4.jar:git-Paper-234]
        at co.aikar.timings.TimedEventExecutor.execute(TimedEventExecutor.java:80) ~[patched_1.14.4.jar:git-Paper-234]
        at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:70) ~[patched_1.14.4.jar:git-Paper-234]
        at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:545) ~[patched_1.14.4.jar:git-Paper-234]
        at net.minecraft.server.v1_14_R1.MinecraftServer.a(MinecraftServer.java:475) ~[patched_1.14.4.jar:git-Paper-234]
        at net.minecraft.server.v1_14_R1.DedicatedServer.init(DedicatedServer.java:290) ~[patched_1.14.4.jar:git-Paper-234]
        at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:876) ~[patched_1.14.4.jar:git-Paper-234]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_221]
Caused by: java.lang.ClassNotFoundException: net.luckperms.api.LuckPerms
        at java.net.URLClassLoader.findClass(Unknown Source) ~[?:1.8.0_221]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_221]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_221]
        ... 13 more