diff --git a/src/TgBotLib/Interfaces/ObjectTypeInterface.php b/src/TgBotLib/Interfaces/ObjectTypeInterface.php
index f64ec4b..4be81e2 100644
--- a/src/TgBotLib/Interfaces/ObjectTypeInterface.php
+++ b/src/TgBotLib/Interfaces/ObjectTypeInterface.php
@@ -7,7 +7,7 @@
         /**
          * Returns an array representation of the object
          *
-         * @return array
+         * @return array|null
          */
         public function toArray(): ?array;