[WildStacker] Plugin WildStacker v2.7.1 generated an exception while executing task 7141
java.util.ConcurrentModificationException: null
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909) ~[?:1.8.0_202]
at java.util.ArrayList$Itr.next(ArrayList.java:859) ~[?:1.8.0_202]
at org.bukkit.craftbukkit.v1_12_R1.CraftWorld.getLivingEntities(CraftWorld.java:646) ~[server.jar:git-Spigot-dcd1643-e60fc34]
at com.bgsoftware.wildstacker.tasks.StackTask.run(StackTask.java:37) ~[?:?]
at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftTask.run(CraftTask.java:76) ~[server.jar:git-Spigot-dcd1643-e60fc34]
at org.bukkit.craftbukkit.v1_12_R1.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:52) [server.jar:git-Spigot-dcd1643-e60fc34]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_202]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_202]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_202]