What does the INVREP trouble mean on an NFS-320, and what are the most likely causes when a single device shows this after being replaced?

The INVREP trouble indicates that a device has returned a response to the panel that the panel did not recognize (Page 68) [1].

When this occurs after replacing a single device, the most likely causes are incorrect addressing, wiring issues, or a problem with the device's functionality (Page 68) [1].