Prey overwrote my new device as the stolen one

This is a known issue when hardware information is shared between devices or, in iOS case, when devices with the same OS get their information synced via iCloud. As a consequence, they share the same entry on your account, and, if you save them as Missing, the overwritten device will start reporting too.

To fix this, just go to the Device Management tab on your Prey account, and disable the ‘Identify devices when linking. Overwrite devices if their hardware information already exists on this account.’

Once you save changes, uninstall the app completely from the new device, then reinstall and configure it typing your password with the app open from the device you’ll add to your devices list again.

What can I do if my stolen phone keeps showing my new device's information?

First of all, avoid panicking. This is normal behavior and it’s because your old and new phones were already detected as one, but the problem will revert on its own. As soon as the stolen device connects with our servers, its information will be updated to the original one. Just make sure you keep the old device entry and wait for it to start reporting.