diff --git a/tools/generate-blockstate-upgrade-schema.php b/tools/generate-blockstate-upgrade-schema.php
index 6fa2d5b72..85d42a35b 100644
--- a/tools/generate-blockstate-upgrade-schema.php
+++ b/tools/generate-blockstate-upgrade-schema.php
@@ -30,7 +30,6 @@ use pocketmine\data\bedrock\block\upgrade\BlockStateUpgradeSchemaUtils;
 use pocketmine\data\bedrock\block\upgrade\BlockStateUpgradeSchemaValueRemap;
 use pocketmine\nbt\tag\Tag;
 use pocketmine\network\mcpe\protocol\serializer\NetworkNbtSerializer;
-use pocketmine\utils\AssumptionFailedError;
 use pocketmine\utils\Filesystem;
 use pocketmine\utils\Utils;
 use function array_key_first;