SAMD21 doesn't wake up after deep sleep

Question

I'am working on a personnal board build with an atsamd21e18a. I'am actually working on sleep mode. I make a function to put samd21 in sleep mode like that. I use RTCZero library.

So in my setup function I've something like this

RTCZero rtc;

void setup(){
    // Set the XOSC32K to run in standby
    SYSCTRL->XOSC32K.bit.RUNSTDBY = 1;

    rtc.begin();   
    .... other line code ....
    attachInterrupt(digitalPinToInterrupt(PIN_USER_BUTTON), wakeUpButtonUser, CHANGE);
    ...other line....
}

So in my setup I intialise rtc and I attach an interrupt in my user button. This button is used to power on or power off my board.

My function goTosleep() :

SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;
__DSB();
__WFI();

In my function wakeUpButtonUser I have a simple if/else statement. If the user pressed the button more than 3 seconds samd21 go to sleep with goToSleep() function, else if it's less than 3 seconds I want wake up the board and light up my led but it's doesn't work.

Here my wakeUpButtonUser function, user_button is object create from C++ for my button.

void wakeUpButtonUser(){
  if (userButton.isPressed())
  {
    userButton.setTimeStartPressed(millis());
    PRINT_DEBUG_LN("Pressed");
  }
  else
  {
    userButton.setTimeEndPressed(millis());
    PRINT_DEBUG_LN("Released");
    uint32_t time_pressed = userButton.getTimePressed();
    if (time_pressed >= temps_on && time_pressed < temps_off)
    {                  
        PRINT_DEBUG_LN("ON");
         //here I have code to light up a led
    }
    else
    {
        PRINT_DEBUG_LN("STOP");
        goSleepMode();
    }
  }
}

This fuction works because if I comment the line goToSleep(), I can read on my serial ON or OFF depending the time I pressed my button and the led works also because I can light up led before going to sleep. But when my board go to sleep, she's never wake up I don't understand why, I missed something?