diff --git a/src/Traits/OverloadingGetter.php b/src/Traits/OverloadingGetter.php
index 633df97..8a635c9 100644
--- a/src/Traits/OverloadingGetter.php
+++ b/src/Traits/OverloadingGetter.php
@@ -68,7 +68,7 @@ trait OverloadingGetter
      */
     public function __isset(string $property): bool
     {
-        $value = $this->__get($property);
+        $value = $this->_data[$property] ?? null;
         return boolval($value) !== false;
     }
 }
diff --git a/src/Traits/TypeChecker.php b/src/Traits/TypeChecker.php
index 9a2042a..8fb8d55 100644
--- a/src/Traits/TypeChecker.php
+++ b/src/Traits/TypeChecker.php
@@ -96,10 +96,10 @@ trait TypeChecker
      */
     public function hasAllowedType(mixed $value): bool
     {
-        if (count($this->getAllowedTypes()) === 0) {
+        if (count($this->_allowedTypes) === 0) {
             return true;
         }
-        foreach ($this->getAllowedTypes() as $type) {
+        foreach ($this->_allowedTypes as $type) {
             $function = 'is_' . $type;
             if (function_exists($function) && $function($value)) {
                 return true;
@@ -124,7 +124,7 @@ trait TypeChecker
      */
     public function isAllowedType(string $type): bool
     {
-        return in_array($type, $this->getAllowedTypes(), true);
+        return in_array($type, $this->_allowedTypes, true);
     }
 
     /**