diff --git a/src/Monolog/Handler/FlowdockHandler.php b/src/Monolog/Handler/FlowdockHandler.php
index c9e97cfe..67d12918 100644
--- a/src/Monolog/Handler/FlowdockHandler.php
+++ b/src/Monolog/Handler/FlowdockHandler.php
@@ -64,6 +64,8 @@ class FlowdockHandler extends SocketHandler
 
     /**
      * Gets the default formatter.
+     *
+     * @suppress PhanTypeMissingReturn
      */
     protected function getDefaultFormatter(): FormatterInterface
     {