Error: 404 Not Found

Sorry, the requested URL 'http://u.limo/wp-admin/admin-ajax.php?channel_id=social_wechat&action=xh_social_channel&tab=login_redirect_to_authorization_uri&xh_social_channel=eb763ed831&notice_str=1731535985&hash=ae6f81a16019bbfc2ee47f00559fd5fb&redirect_to=https%3A%2F%2Fu.limo%2Ftag%2F%25E5%25BF%25AB%25E9%2597%25AA%2F' caused an error:

Not found: '/wp-admin/admin-ajax.php'