Your version is past EOL. You should upgrade to either the latest version or the current LTA (long-term active version) at your earliest convenience. Your upgrade path is:
If we upgrade to Release 25.5.0.107428, will we lose the current configurations on the SonarQube dashboard, including project-specific settings, templated configurations, and rule customizations?
We later resolved the issue by restarting the SonarQube server, after which the scans began running successfully. If we continue using this version, is there any risk that it might be deprecated, removed, or stop functioning unexpectedly from Sonar’s end?
If you follow the upgrade guide, you won’t lose any data! Of course, a backup will make sure that if something goes wrong you can start over.
It’s EOL software. There’s a big red banner on your instance telling you that. It will receive no patches (no new features, improvements to performance or analysis results), and the only answer you’ll get in this forum is “Upgrade”