If you get those with an ID rather than a device name, this is most likely an orphaned device - you can check in My Devices whether you actually do have a device with that ID. If not, you can remove it by following these steps (I just did that to remove the ten or so orphaned devices I had and after three more network repairs, I was able to get the network repaired without any errors):
- Go to My Devices
- Click “New Device” at the top right
- Enter some obvious name (I just used “Trash”), put the orphaned network ID into the “Device Network ID” field, select “Z-Wave Device” as the type, and select your location and hub
- Click “Create”
- In the mobile app, go to this newly created device (you might have to refresh the device list), select “Edit Device” and force-remove the device
This will remove the orphaned associations from the hub and no longer cause the hub to look for non-existent devices.