Aeotec Dual Nano switch 2 devices

I have had the Aeotec Dual Nano switch operate my garage electric heater for a couple of years, worked perfectly. Upgrading from a v1 hub to v3, having to re-connect, now it becomes 2 devices, one for each switch I suspect. Before it was 1 device that operated both switches.
Also I can neither turn the switched off or on with ST, I’m getting a server error. There may be a firmware update for the Nano, I have to look into that yet. So Iy could be a Aeotec issue or a ST issue.