diff --git a/includes/model/class-activity.php b/includes/model/class-activity.php
index 1bdf660..f865d6d 100644
--- a/includes/model/class-activity.php
+++ b/includes/model/class-activity.php
@@ -53,8 +53,8 @@ class Activity {
 		}
 		$this->cc = array( \get_rest_url( null, '/activitypub/1.0/users/' . intval( $post->get_post_author() ) . '/followers' ) );
 
-		if ( isset( $object['attributedTo'] ) ) {
-			$this->actor = $object['attributedTo'];
+		if ( isset( $this->object['attributedTo'] ) ) {
+			$this->actor = $this->object['attributedTo'];
 		}
 
 		foreach ( $post->get_tags() as $tag ) {
@@ -65,8 +65,8 @@ class Activity {
 
 		$type = \strtolower( $this->type );
 
-		if ( isset( $object['id'] ) ) {
-			$this->id = add_query_arg( 'activity', $type, $object['id'] );
+		if ( isset( $this->object['id'] ) ) {
+			$this->id = add_query_arg( 'activity', $type, $this->object['id'] );
 		}
 	}
 
diff --git a/tests/test-class-activitypub-activity-dispatcher.php b/tests/test-class-activitypub-activity-dispatcher.php
index d34a24e..6693ba1 100644
--- a/tests/test-class-activitypub-activity-dispatcher.php
+++ b/tests/test-class-activitypub-activity-dispatcher.php
@@ -34,6 +34,7 @@ class Test_Activitypub_Activity_Dispatcher extends ActivityPub_TestCase_Cache_HT
 		$all_args = $pre_http_request->get_args();
 		$first_call_args = array_shift( $all_args );
 		$this->assertEquals( 'https://example.com/author/jon/inbox', $first_call_args[2] );
+
 		$second_call_args = array_shift( $all_args );
 		$this->assertEquals( 'https://example.org/users/username/inbox', $second_call_args[2] );
 
@@ -73,6 +74,9 @@ class Test_Activitypub_Activity_Dispatcher extends ActivityPub_TestCase_Cache_HT
 		$first_call_args = $all_args[0];
 		$this->assertEquals( 'https://example.com/alex/inbox', $first_call_args[2] );
 
+		$body = json_decode( $first_call_args[1]['body'], true );
+		$this->assertArrayHasKey( 'id', $body );
+
 		remove_all_filters( 'activitypub_from_post_object' );
 		remove_filter( 'pre_http_request', array( $pre_http_request, 'filter' ), 10 );
 	}