I am slowly figuring out how to use the Librem 5 phone (running pureos). My current problem is how to move files from the computer on my desk (running KDE Neon 5.21, KDE Plasma 5.21.4) to the phone. I installed KDE Connect on the phone (it is already on the desktop) plugged in a usb connection and enabled Bluetooth on both devices. Now KDE connect on the desktop invites me to "pair a device," then says "No device selected" and does not indicate that it can see any device. KDE Connect on the phone just shows a blank screen. (With the wired connection, the desktop just says "IP connection was unavailable.") Can somebody point me to a description of how to make this connection, with KDE connect or otherwise?

The phone is not running Android, but an actual desktop Linux desktop OS, and there does not seem to be a way to attempt such a connection even manually via IP address as you can from an Android device to a desktop. At least not an obvious one.

Maybe check any firewall settings on both devices to make sure nothing is being blocked.