diff --git a/src/Tarosky/TSCF/UI/Fields/Input.php b/src/Tarosky/TSCF/UI/Fields/Input.php
index 062e868..ada52bf 100644
--- a/src/Tarosky/TSCF/UI/Fields/Input.php
+++ b/src/Tarosky/TSCF/UI/Fields/Input.php
@@ -187,7 +187,7 @@ public function save_data() {
 	 * @return mixed
 	 */
 	protected function normalize_save_data( $data ) {
-		return $data;
+		return $data ?? '';
 	}
 
 	/**