Error occurred while disabling AxGraves v1.13.6

[servicomcr]

[17:03:24 ERROR]: Error occurred while disabling AxGraves v1.13.6
java.lang.NullPointerException: Cannot invoke "com.artillexstudios.axgraves.libs.axapi.packetentity.PacketEntity.remove()" because the return value of "com.artillexstudios.axgraves.grave.Grave.getEntity()" is null
at AxGraves-1.13.6.jar/com.artillexstudios.axgraves.AxGraves.disable(AxGraves.java:71) ~[AxGraves-1.13.6.jar:?]
at AxGraves-1.13.6.jar/com.artillexstudios.axgraves.libs.axapi.AxPlugin.onDisable(AxPlugin.java:156) ~[AxGraves-1.13.6.jar:?]
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:291) ~[paper-mojangapi-1.21-R0.1-SNAPSHOT.jar:?]
at io.papermc.paper.plugin.manager.PaperPluginInstanceManager.disablePlugin(PaperPluginInstanceManager.java:237) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at io.papermc.paper.plugin.manager.PaperPluginInstanceManager.disablePlugins(PaperPluginInstanceManager.java:161) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at io.papermc.paper.plugin.manager.PaperPluginManagerImpl.disablePlugins(PaperPluginManagerImpl.java:97) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at org.bukkit.plugin.SimplePluginManager.disablePlugins(SimplePluginManager.java:541) ~[paper-mojangapi-1.21-R0.1-SNAPSHOT.jar:?]
at org.bukkit.craftbukkit.CraftServer.disablePlugins(CraftServer.java:623) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at net.minecraft.server.MinecraftServer.stopServer(MinecraftServer.java:1057) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at net.minecraft.server.dedicated.DedicatedServer.stopServer(DedicatedServer.java:883) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at net.minecraft.server.MinecraftServer.runServer(MinecraftServer.java:1388) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at net.minecraft.server.MinecraftServer.lambda$spin$0(MinecraftServer.java:333) ~[purpur-1.21.jar:1.21-2272-b2d1fea]
at java.base/java.lang.Thread.run(Thread.java:1583) ~[?:?]

[BenceX100]

Should be fixed in the latest version