diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f49e82a..ede1bb6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -146,7 +146,7 @@ jobs:
     runs-on: macos-${{ matrix.version }}
     strategy:
       matrix:
-        version: [10.15]
+        version: [13]
     steps:
       # Force PHP to 8.0
       # Doing this because tests fail in PHP 8.1 (default on macos Github Runner as of Dec 2021)
diff --git a/src/AWS/CRT/HTTP/Request.php b/src/AWS/CRT/HTTP/Request.php
index 9b4f07c..bec4ac1 100644
--- a/src/AWS/CRT/HTTP/Request.php
+++ b/src/AWS/CRT/HTTP/Request.php
@@ -13,7 +13,7 @@ class Request extends Message {
     public function __construct($method, $path, $query = [], $headers = [], $body_stream = null) {
         parent::__construct($method, $path, $query, $headers);
         if (!is_null($body_stream) && !($body_stream instanceof InputStream)) {
-            throw InvalidArgumentException('body_stream must be an instance of ' . InputStream::class);
+            throw new \InvalidArgumentException('body_stream must be an instance of ' . InputStream::class);
         }
         $this->body_stream = $body_stream;
     }