After reboot, log back in. Check:
Recommendation: If the device is ISP-managed and firmware cannot be updated, isolate IoT devices behind the HG8345r and disable remote management (WAN-side access). hg8345r firmware top
Navigate to Management → Backup & Restore → Click Backup Configuration. Save the .cfg file to your PC. If the new firmware fails, you can restore this. After reboot, log back in