The serial number has already been registered error

To resolve this error:

This error message indicates that this unit’s record (registration) already exists under another network. Since only one B-Deploy record (registration) is allowed, the unit’s record must be deleted from the BrightAuthor:connected both under Admin> Device Provisioning tab and from under the Network section in the original network.

Only the owner of the network where the device is registered can remove the serial number from the network and provisioning record. If necessary, contact that network owner so they can make these changes.