Error: The repository '...' is no longer signed

Hi, I wanted to update trinity today (Ubuntu 18.04) and got this message: Err:7 http://mirror.xcer.cz/trinity-sb bionic InRelease 403 Forbidden [IP: 91.241.23.210 80] Hit:8 https://packages.cisofy.com/community/lynis/deb stable InRelease Reading package lists... Done E: Failed to fetch http://mirror.xcer.cz/trinity-sb/dists/bionic/InRelease 403 Forbidden [IP: 91.241.23.210 80] E: The repository 'http://mirror.xcer.cz/trinity-sb bionic InRelease' is no longer signed. I went to the wiki (Preliminary Stable Builds) and rerun the GPG key import, but it looks like I already had it: sudo apt-key adv --keyserver pool.sks-keyservers.net --recv-key A04BE668 Executing: /tmp/apt-key-gpghome.fCUStJLtMA/gpg.1.sh --keyserver pool.sks-keyservers.net --recv-key A04BE668 gpg: key 608F5293A04BE668: 7 signatures not checked due to missing keys gpg: key 608F5293A04BE668: "Slávek Banko <slavek.banko(a)axis.cz>" not changed gpg: Total number processed: 1 gpg: unchanged: 1 Is everybody able to update? Thanks in advance, -- Diego.