The issue described generally indicates that the Bluetooth connection is paired in a way that prevents other connection types.
Please try the following:
- Close Silhouette Studio
- Clear your Silhouette Studio Preferences (see Manually Clear Silhouette Studio Preference Folder)
- On your Mac, choose Apple menu > System Settings > Bluetooth
- Disconnect the pairing for the Silhouette Cameo device
- Connect your Silhouette machine to your computer via a USB cord
- Open Silhouette Studio
- Go to the Send panel to check the machine connection status