Even if the Node is not accessible in the given network, it can be reconfigured to factory settings by the CATS service tool as follows:
● Connect CATS to the Node (IQRF IDE, menu Tools / CATS Service Tools / DPA Service Mode).
● Click the Factory Settings button.
● Reset the Node (e.g. by switching the power supply off and on).
Refer to the IQRF IDE Help, chapter DPA Service Mode.