diff --git a/src/pocketmine/command/SimpleCommandMap.php b/src/pocketmine/command/SimpleCommandMap.php
index bbaca362a..efb51a7f6 100644
--- a/src/pocketmine/command/SimpleCommandMap.php
+++ b/src/pocketmine/command/SimpleCommandMap.php
@@ -148,7 +148,7 @@ class SimpleCommandMap implements CommandMap{
 			return false;
 		}
 
-		if(isset($this->knownCommands[$label]) and $this->knownCommands[$label]->getLabel() === $label){
+		if(isset($this->knownCommands[$label]) and $this->knownCommands[$label]->getLabel() !== null and $this->knownCommands[$label]->getLabel() === $label){
 			return false;
 		}