diff --git a/app/Http/Controllers/ImportController.php b/app/Http/Controllers/ImportController.php
index b9e28d35ec..2331cc37e8 100644
--- a/app/Http/Controllers/ImportController.php
+++ b/app/Http/Controllers/ImportController.php
@@ -35,7 +35,7 @@ class ImportController extends BaseController
             if ($request->hasFile($fileName)) {
                 $file = $request->file($fileName);
                 $destinationPath = env('FILE_IMPORT_PATH') ?: storage_path() . '/import';
-                $extension = $file->getClientOriginalExtension();
+                $extension = strtolower($file->getClientOriginalExtension());
 
                 if ($source === IMPORT_CSV) {
                     if ($extension != 'csv') {