Adafruit feather M0 low power

I am trying to operate adafruit feather m0 on deepsleep mode and wake after time interrupt. I use arduino low power library. The microcontroller is suppsoed to consume only 300uA in deepsleep but i can achieve only 2.7 mA. If i put all pins to low, it goes down to 1.3mA but nothing less. Has anyone tried deepsleep in this board. Any help is appreciated.

void setup() {
pinMode(LED_BUILTIN, OUTPUT);
// Uncomment this function if you wish to attach function dummy when RTC wakes up the chip
LowPower.attachInterruptWakeup(RTC_ALARM_WAKEUP, dummy, CHANGE);
}

void loop() {
digitalWrite(LED_BUILTIN, HIGH);
delay(500);
digitalWrite(LED_BUILTIN, LOW);
delay(500);
// Triggers a 20000 ms sleep (the device will be woken up only by the registered wakeup sources and by internal RTC)
// The power consumption of the chip will drop consistently
LowPower.deepSleep(20000);
}

void dummy() {
int i = 10;
}

The microcontroller is suppsoed to consume only 300uA in deepsleep

The microcontroller but not the board. Did you check all other components on the board for their low power state?

How do you power the board? If you power it by 5V you loose most of the power in the voltage regulator.