Wio GPS Board and Arduino Due


I am trying to get data from an Arduino Due to a Wio GPS board. I am using the following code:

#include <SoftwareSerial.h>
SoftwareSerial ser_serial(A0,A1);

GPSTracker gpsTracker = GPSTracker();

void setup() {
pinMode(12, OUTPUT);
digitalWrite(12, HIGH);
serialByte = ser_serial.read();

My problem is that I receive the following message on the serial monitor: MAL POWER DOWN

I have connected the A0, A1 pins to TX, RX of the Due and the related grounds.

What am I doing wrong?

Any suggestions?