Index: /controller/wpsg_SystemController.class.php
===================================================================
--- /controller/wpsg_SystemController.class.php	(revision 8206)
+++ /controller/wpsg_SystemController.class.php	(revision 8207)
@@ -153,5 +153,5 @@
 
 			$arOptions = [
-                'body' => http_build_query($post_data, null, '&')
+                'body' => http_build_query($post_data, '', '&')
             ];