diff --git a/application/api/controller/Ota.php b/application/api/controller/Ota.php
index 9f09005..96e81ef 100644
--- a/application/api/controller/Ota.php
+++ b/application/api/controller/Ota.php
@@ -131,7 +131,7 @@ class Ota extends Api
      */
     private function calculateFileInfo($relativePath)
     {
-        $fullPath = root_path() . 'public' . DIRECTORY_SEPARATOR . 'uploads' . DIRECTORY_SEPARATOR . ltrim($relativePath, '/');
+        $fullPath = ROOT_PATH . 'public' . DIRECTORY_SEPARATOR . 'uploads' . DIRECTORY_SEPARATOR . ltrim($relativePath, '/');
         if (!file_exists($fullPath)) {
             return null;
         }