Power supply issue. Check two things.
First, verify the appliance is plugged into a live mains socket. Second, locate the main switch on the back of the machine. Ensure it is in the I (on) position.
If it's plugged in and the main switch is on, the problem is internal. Unplug the machine. Do not remove the cover. Contact De'Longhi Customer Services for repair.
Safety: Never operate the appliance with a damaged cord or plug. Do not attempt to repair the internal electronics yourself.