#include <M5ez.h>
#include <M5Stack.h>

void setup() {
ez.begin();
M5.Power.begin();
M5.Power.setLowPowerShutdownTime(ShutdownTime::SHUTDOWN_16S);
}

void loop() {
ez.msgBox("M5ez minimal program", "Hello World !", "Settings");
ez.settings.menu();
}

When I compile I get the error "exit status 1 'ShutdownTime' has not been declared"

What am I doing wrong?

What I am trying to do is to have the M5Stack Gray stay on for a short time after the USB is unplugged. At the moment when the USB is unplugged the M5 resets and then restarts.