[21:58:22 WARN]: [Vault] Task #14 for Vault v1.7.1-b91 generated an exception
java.util.ConcurrentModificationException: null
        at java.util.HashMap$HashIterator.nextNode(HashMap.java:1442) ~[?:1.8.0_161]
        at java.util.HashMap$KeyIterator.next(HashMap.java:1466) ~[?:1.8.0_161]
        at org.bukkit.permissions.PermissibleBase.clearPermissions(PermissibleBase.java:168) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.permissions.PermissibleBase.recalculatePermissions(PermissibleBase.java:149) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.plugin.SimplePluginManager.dirtyPermissibles(SimplePluginManager.java:689) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.plugin.SimplePluginManager.calculatePermissionDefault(SimplePluginManager.java:668) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.plugin.SimplePluginManager.addPermission(SimplePluginManager.java:640) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.plugin.SimplePluginManager.addPermission(SimplePluginManager.java:628) ~[patched_1.12.2.jar:git-Paper-1534]
        at net.milkbowl.vault.Vault$1.run(Vault.java:155) ~[?:?]
        at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftTask.run(CraftTask.java:63) ~[patched_1.12.2.jar:git-Paper-1534]
        at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:423) ~[patched_1.12.2.jar:git-Paper-1534]
        at net.minecraft.server.v1_12_R1.MinecraftServer.D(MinecraftServer.java:839) ~[patched_1.12.2.jar:git-Paper-1534]
        at net.minecraft.server.v1_12_R1.DedicatedServer.D(DedicatedServer.java:423) ~[patched_1.12.2.jar:git-Paper-1534]
        at net.minecraft.server.v1_12_R1.MinecraftServer.C(MinecraftServer.java:773) ~[patched_1.12.2.jar:git-Paper-1534]
        at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:665) ~[patched_1.12.2.jar:git-Paper-1534]
        at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161]