Our tracker got the scrape function switched off for increased privacy. A torrent client has to join the swarm as "active" peer to get information on the peers. If the torrent is just queued, a scrape error will be shown. So if your torrents are just queued, it is "normal" and you might change the priority settings or force start to get them running.
If your torrents are in "Seeding" or "Downloading" status (means not queued downloading or seeding), the cause is another and we have to look for other solutions than starting them.