diff --git a/src/OpenApi/Model/Parameter.php b/src/OpenApi/Model/Parameter.php
index ef45d46a140..f68f0cbd231 100644
--- a/src/OpenApi/Model/Parameter.php
+++ b/src/OpenApi/Model/Parameter.php
@@ -56,12 +56,12 @@ public function __construct(string $name, string $in, string $description = '',
         }
     }
 
-    public function getName(): string
+    public function getName(): ?string
     {
         return $this->name;
     }
 
-    public function getIn(): string
+    public function getIn(): ?string
     {
         return $this->in;
     }
@@ -91,7 +91,7 @@ public function getSchema(): array
         return $this->schema;
     }
 
-    public function getStyle(): ?string
+    public function getStyle(): string
     {
         return $this->style;
     }