Error

org.bukkit.event.EventException: null
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:298) ~[spigot.jar:git-Bukkit-b5a10a9]
	at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62) ~[spigot.jar:git-Bukkit-b5a10a9]
	at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:499) [spigot.jar:git-Bukkit-b5a10a9]
	at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:484) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.PlayerList.onPlayerJoin(PlayerList.java:330) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.PlayerList.a(PlayerList.java:151) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.LoginListener.b(LoginListener.java:131) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.LoginListener.e(LoginListener.java:57) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.NetworkManager.a(NetworkManager.java:224) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.ServerConnection.c(SourceFile:187) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:768) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:371) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:651) [spigot.jar:git-Bukkit-b5a10a9]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:555) [spigot.jar:git-Bukkit-b5a10a9]
	at java.lang.Thread.run(Unknown Source) [?:?]
Caused by: java.lang.NoSuchFieldError: recentTps
	at com.extendedclip.papi.expansion.server.nms.NMS_1_12_R1.getTps(NMS_1_12_R1.java:10) ~[?:?]
	at com.extendedclip.papi.expansion.server.ServerExpansion.getTps(ServerExpansion.java:117) ~[?:?]
	at com.extendedclip.papi.expansion.server.ServerExpansion.onPlaceholderRequest(ServerExpansion.java:151) ~[?:?]
	at me.clip.placeholderapi.PlaceholderAPI.setPlaceholders(PlaceholderAPI.java:342) ~[?:?]
	at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
	at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:?]
	at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:?]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[?:?]
	at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:296) ~[spigot.jar:git-Bukkit-b5a10a9]
	... 14 more