RankMath Issue

Hello,
Im using your progin with RankMath seo but I see some problems.

I have added this code to functions.php but I see this error in the snippet test:

“Invalid object type for fielnd “itemReviewed””

Can you help me please fix Snippet code to be valind with RankMath for products and articles visitor’s rankings?

add_filter( "rank_math/snippet/rich_snippet_product_entity", "custom_kksr_rating");

function custom_kksr_rating ( $entity ) {
	
	$id = get_the_ID();
	$temprend = get_post_meta('kksr_sd');
	//var_dump($temprend);

	$i = get_post_meta($id, '_kksr_casts', true ); 
	$sumstar = get_post_meta($id, '_kksr_ratings', true ); 
	$star = round($sumstar / $i);
		
		$entity['aggregateRating'] = [
		"@type" => "AggregateRating",
		"ratingValue" => "$star",
		"reviewCount" => "$i",
	];
	//var_dump($entity);
	return $entity;	
}

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