For DiO First and nano version sockets:

You need the remote control with the group function (G).
Put your socket in learn mode and disconnect it from the power for 10 seconds and then reconnect it.  Then, press the OFF (0) button of the "G" function of your remote control, this will completely delete the memory of your socket.

If you do not have this remote control, it will be necessary to delete each remote control, wireless switch, detector and/or channel individually, following the same procedure.   

For modules and other sockets:

At any time, you can reinitialise your receiver by pressing its "learn" button for 6-10 seconds until the LED starts to flash rapidly. At this point, press the same button again briefly. The light connected to the receiver will then flash twice to confirm that the receiver has been reset. In case of a shutter, it should confirm the reset by moving to-and-fro.

Notice: This operation deletes the entire memory of the receiver and allows it to "reset"