Include custom post types in category queries. Add this to functions.php
//Include custom post types in category queries
function add_custom_types_to_tax( $query ) {
if( is_category() || is_tag() && empty( $query->query_vars['suppress_filters'] ) ) {
// Get all your post types
$post_types = get_post_types();
$query->set( 'post_type', $post_types );
return $query;
}
}
add_filter( 'pre_get_posts', 'add_custom_types_to_tax' );