What is it you're trying to do here? Do you want a device to report to two different databases?
If not, by default, the device will only communicate to one database. We don't suggest having two devices in two databases as it is possible that it can communicate to one or the other. If you want the device to, lets's say, communicate to database 2, you will need to delete the device from database 1, or make historical to keep the data stored in database 1.