// Action Function to get Sidebars through Ajax Call
function prefix_ajax_get_metadata() {
    $postid= $_REQUEST['postid'];
    $data = get_post_meta( $postid );
    echo $data['wccpf_authorvalue'];
    die();
}
add_action( 'wp_ajax_get_metadata', 'prefix_ajax_get_metadata' );
add_action('wp_ajax_nopriv_get_metadata', 'prefix_ajax_get_metadata');