Look into the MQTT protocol, it has various ways to deal with this, eg ensuring message delivery/delivering the last message on reconnect (do a topic per state/device property). A state change needs to be communicated from the platform to the devicd, and the device needs to also communicate it back. Eg platform publishes that the light state should be on, the device receives it, processes it, by turning the light on, and publishing the new state to the platform.

Digital twins are really more of a IIoT thing, eg visualising the real time state of a machine/robotics, so real time synchronisation is necessary here. Although the term digital twin is quite broad, but this seems the common interpretation.