AVR Freaks

I'm currently working on a SAME70 board made by Atmel. I plugged on it an extention OLED1 board (Atmel too) on EXT1 port. My goal is to recover the information about interrupt type (falling or raising) when I'm pressing the button 3 on OLED1 board. I have a function which allows me to set the different registers related to an interrupts. But unfortunately the register which indicates the polarity (FLHSR) stay always at 0 whatever the state of the button. Below my code.

#include <asf.h>

void set_Interupt_Pin()
{
    uint32_t mask = 1 << 19;  /*bitmasking*/
    PIOA->PIO_IER = mask;    /*enable interruptions*/
    PIOA->PIO_AIMER = mask;  /*add new interruption*/
    PIOA->PIO_ESR = mask;     /*set interrupt source on edge*/
    PIOA->PIO_REHLSR = mask; /* set interrupt to rising edge*/
    PIOA->PIO_FELLSR= mask; /* set interrupt to falling edge*/
    NVIC_DisableIRQ(ID_PIOA);
    NVIC_ClearPendingIRQ(ID_PIOA);
    NVIC_EnableIRQ(ID_PIOA);   /*set NVIC to get interruptions from PIOA*/
    NVIC_SetPriority(ID_PIOA, 4); /*priority 4*/
    
}

void PIOA_Handler(void)
{
    printf("FRLHSR: %x\n",PIOA->PIO_FRLHSR); /*state of polarity event */
    printf("ISR: %x\n",PIOA->PIO_ISR); 
    printf("ELSR: %x\n",PIOA->PIO_ELSR); 
    printf("AIMMR: %x\n",PIOA->PIO_AIMMR); 
}

int main(void)
{
    const usart_serial_options_t usart_serial_options = {
        .baudrate     = CONF_UART_BAUDRATE,
        .charlength   = CONF_UART_CHAR_LENGTH,
        .paritytype   = CONF_UART_PARITY,
        .stopbits     = CONF_UART_STOP_BITS
    };
    sysclk_init();
    board_init();
    stdio_serial_init(CONF_UART, &usart_serial_options);
    set_Interupt_Pin();
    while(1){}
}

You can see here the result of print when I press button (first part) and I release button (second part).