SUMMARY
The pairing between two computers running KDE is lost when either one of them leaves the network (e.g. is suspended, rebooted, etc) or if one hits "refresh" in the KDE Connect KCM, thus forcing the user to constantly re-pairing the devices.

STEPS TO REPRODUCE
1. use two computers with KDE Connect installed
2. pair them
3. hit "refresh" on one of them from the KDE Connect KCM

OBSERVED RESULT
The devices become unpaired, with the certificate and the other info being removed from the "trusted_devices" file in ~/.config/kdeconnect. This is reproducible every time.

EXPECTED RESULT
The devices stay paired.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: KDE neon 5.19.5 (based on Ubuntu Focal)
KDE Plasma Version: KDE 5.19.5
KDE Frameworks Version: 5.74.0
Qt Version: 5.15.0
KDE Connect version: 20.08.1

ADDITIONAL INFORMATION
This behaviour persists removing KDE Connect configuration and reboots. It also manifests itself in the impossibility to transfer files: the transfer begins, but is never actually carried out, with the receiving side showing the transfer notification which stays there indefinitely.