sudo apt update
Get:1 http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04  InRelease [1548 B]
Hit:2 http://ppa.launchpad.net/alexlarsson/flatpak/ubuntu disco InRelease                                                                            
Hit:3 http://dl.google.com/linux/chrome/deb stable InRelease                                                                                         
Hit:4 http://archive.canonical.com/ubuntu groovy InRelease                                                                                           
Hit:5 http://de.archive.ubuntu.com/ubuntu groovy InRelease                                                                                           
Hit:6 http://repository.spotify.com stable InRelease                                                                                                 
Ign:7 http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy InRelease                                                            
Hit:8 http://packages.microsoft.com/repos/code stable InRelease                                                                                      
Hit:9 http://de.archive.ubuntu.com/ubuntu groovy-updates InRelease                                                                                   
Hit:10 https://deb.opera.com/opera-stable stable InRelease                                                                                           
Hit:11 http://de.archive.ubuntu.com/ubuntu groovy-security InRelease                                                                                 
Hit:12 https://ftp.gajim.org/debian unstable InRelease                                                                                               
Hit:13 https://brave-browser-apt-release.s3.brave.com stable InRelease                                             
Hit:14 http://ppa.launchpad.net/quiterss/quiterss/ubuntu focal InRelease                                           
Hit:15 http://de.archive.ubuntu.com/ubuntu groovy-backports InRelease                        
Hit:16 https://repo.skype.com/deb stable InRelease                                                
Hit:17 http://ppa.launchpad.net/vincent-vandevyvre/vvv/ubuntu eoan InRelease                      
Err:18 http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy Release
  404  Not Found [IP: 91.189.95.85 80]
Err:1 http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04  InRelease
  The following signatures were invalid: EXPKEYSIG 0FAD31CA8719FCE4 home:stevenpusser OBS Project <home:stevenpusser@build.opensuse.org>
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04  InRelease: The following signatures were invalid: EXPKEYSIG 0FAD31CA8719FCE4 home:stevenpusser OBS Project <home:stevenpusser@build.opensuse.org>