I had a similar problem recently on windows. Qbittorrent (version 4.5.3 ish? Don’t quote me) bound to paid proton VPN. Torrents would be added automatically by sonarr, but remain “stalled” until I restarted qbittorrent with administrator permissions. It would work for a day before it stalled out again and I had to manually restart it. Happened for months. Never figured out why.