Just when did this happen? On a new install? Did you do the install? I would suspect malware is involved - are you using any malware/spam protective software?

Are you using Mint or another Linux distro like it?

Package builds of Firefox from Linux distros are updated in the distro package updates manager and not updated by Mozilla.

Instead of removing the check for updates and having no message there, distros like Mint add the managed by your organization message which may confuse some people. https://blog.linuxmint.com/?p=4244

Btw your version of Firefox 102 is old. If you are not able to find new updates in updates package manager then your version of Linux may be EOL in package updates support.

MOzilla only provides internal Firefox updates to their own Firefox builds from Windows, macOS, Linux from mozilla.org like say https://www.mozilla.org/firefox/all/