diff --git a/src/Jobs.php b/src/Jobs.php
index b541581..1698c8b 100644
--- a/src/Jobs.php
+++ b/src/Jobs.php
@@ -123,7 +123,7 @@ private function toStringOfStringMap(array $map): array
                 \is_string($value) => $value,
                 \is_bool($value) => $value ? 'true' : 'false',
                 $value instanceof \JsonSerializable,
-                \is_array($value) => \json_encode($value, \JSON_THROW_ON_ERROR),
+                \is_array($value) => \json_encode($value, \JSON_THROW_ON_ERROR | (empty($value)? \JSON_FORCE_OBJECT : 0)),
                 default => throw new \InvalidArgumentException(
                     \sprintf('Can not cast to string unrecognized value of type %s', \get_debug_type($value)),
                 ),
diff --git a/src/Queue/AMQP/ExchangeType.php b/src/Queue/AMQP/ExchangeType.php
index 4a1cea5..53d02ef 100644
--- a/src/Queue/AMQP/ExchangeType.php
+++ b/src/Queue/AMQP/ExchangeType.php
@@ -22,7 +22,7 @@ enum ExchangeType: string
      * routing by comparing the routing key. But, in this case, the key is set
      * using a template, like "user.*.messages".
      */
-    case Topics = 'topics';
+    case Topics = 'topic';
 
     /**
      * Routes tasks to related queues based on a comparison of the (key, value)