The AppCenter has problems updating. This type of error appears multiple times here, but I think they're all a bit different?
I get the following notice:
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/network:/messaging:/xmpp:/dino/xUbuntu_18.04 InRelease: The following signatures were invalid: EXPKEYSIG 62EB1A0917280DDF network OBS Project <network@build.opensuse.org>
E: http://download.opensuse.org/repositories/network:/messaging:/xmpp:/dino/xUbuntu_18.04 InRelease is not (yet) available (The following signatures were invalid: EXPKEYSIG 62EB1A0917280DDF network OBS Project
This seems more specific than the other questions. Can anybody tell me what went wrong (and how to fix it)?