diff --git a/src/Handles/BvBeJHandle.php b/src/Handles/BvBeJHandle.php
index a330669..34b1b71 100644
--- a/src/Handles/BvBeJHandle.php
+++ b/src/Handles/BvBeJHandle.php
@@ -112,7 +112,7 @@ class BvBeJHandle
         ksort($form);
         $singArr = [];
         foreach ($form as $k => $v) {
-            $singArr[urlencode($k)] = urlencode($v);
+            $singArr[urlencode(strval($k))] = urlencode(strval($v));
         }
         $sign = http_build_query($singArr);
         try {