diff --git a/src/DumpMiddleware.php b/src/DumpMiddleware.php
index 6a80ae7..5362df6 100644
--- a/src/DumpMiddleware.php
+++ b/src/DumpMiddleware.php
@@ -58,7 +58,7 @@ namespace Dump {
                     }
 
                     if (isset($dump)) {
-                        $json = json_encode(array_merge(["_dump" => $dump ], json_decode($body->getContents() ?? "{}", true)), JsonResponse::DEFAULT_JSON_FLAGS);
+                        $json = json_encode(array_merge(["_dump" => $dump ], (array) json_decode($body->getContents() ?? "{}", true)), JsonResponse::DEFAULT_JSON_FLAGS);
 
                         $stream->write(! is_string($json) ? json_encode($json, JsonResponse::DEFAULT_JSON_FLAGS) : $json);
                     }