[09:58:57 WARN]: java.lang.IllegalArgumentException: Cannot drop air
[09:58:57 WARN]:        at com.google.common.base.Preconditions.checkArgument(Preconditions.java:122)
[09:58:57 WARN]:        at net.minecraft.server.v1_14_R1.EntityItem.setItemStack(EntityItem.java:447)
[09:58:57 WARN]:        at org.bukkit.craftbukkit.v1_14_R1.entity.CraftItem.setItemStack(CraftItem.java:35)
[09:58:57 WARN]:        at com.bgsoftware.wildstacker.objects.WStackedItem.setStackAmount(WStackedItem.java:60)
[09:58:57 WARN]:        at com.bgsoftware.wildstacker.objects.WStackedItem.runStack(WStackedItem.java:255)
[09:58:57 WARN]:        at com.bgsoftware.wildstacker.objects.WStackedItem.lambda$runStackAsync$3(WStackedItem.java:222)
[09:58:57 WARN]:        at java.util.ArrayList.forEach(ArrayList.java:1257)
[09:58:57 WARN]:        at com.bgsoftware.wildstacker.utils.threads.StackService$StackServiceWorld$1.run(StackService.java:89)
[09:58:57 WARN]:        at java.util.TimerThread.mainLoop(Timer.java:555)
[09:58:57 WARN]:        at java.util.TimerThread.run(Timer.java:505)