diff --git a/composer.json b/composer.json
index ffb58e7..2764308 100644
--- a/composer.json
+++ b/composer.json
@@ -31,7 +31,7 @@
   },
   "require": {
     "php": ">=7.2",
-    "guzzlehttp/guzzle": "^7.0",
+    "guzzlehttp/guzzle": "^7.15.1",
     "nexmo/client-core": "^2.0"
   }
 }