Link, wake up...

src/main/java/com/drtshock/playervaults/listeners/SignListener.java

@@ -58,6 +58,9 @@ public class SignListener implements Listener {
             return;
         }
         Player player = event.getPlayer();
+        if (player.isSleeping() || player.isDead() || !player.isOnline()) {
+            return;
+        }
         Block block = event.getClickedBlock();
         if (event.getAction() == Action.RIGHT_CLICK_BLOCK) {
             if (PlayerVaults.getInstance().getInVault().containsKey(player.getUniqueId().toString())) {

src/main/java/com/drtshock/playervaults/vaultmanagement/VaultOperations.java

@@ -131,6 +131,9 @@ public class VaultOperations {
         if (isLocked()) {
             return false;
         }
+        if (player.isSleeping() || player.isDead() || !player.isOnline()) {
+            return false;
+        }
         int number;
         try {
             number = Integer.parseInt(arg);
@@ -202,6 +205,10 @@ public class VaultOperations {
             return false;
         }
 
+        if (player.isSleeping() || player.isDead() || !player.isOnline()) {
+            return false;
+        }
+
         long time = System.currentTimeMillis();
 
         int number = 0;