Unable to make USB HS Mass storage run with touchgfx

[Caan]

I have successfully run the USB HS Mass storage on a new project without the use of freertos and touchgfx , But when the touchgfx code  for STM32H750B-DK is modified to run the code I am getting hard faults

static uint8_t usb_done = 0;

extern ApplicationTypeDef Appli_state;
extern USBH_HandleTypeDef hUsbHostHS;
extern FATFS USBHFatFS;
extern char USBHPath[4];

void Debug_Print(char *str)
{
    HAL_UART_Transmit(&huart4, (uint8_t*)str, strlen(str), 100);
}




static uint8_t file_written = 0;

void StartDefaultTask(void *argument)
{
    Debug_Print("Task Started\r\n");

    for(;;)
    {
        USBH_Process(&hUsbHostHS);

        if (Appli_state == APPLICATION_READY && file_written == 0)
        {
            Debug_Print("USB Detected\r\n");

            if (USBH_MSC_IsReady(&hUsbHostHS))
            {
                Debug_Print("MSC Ready\r\n");

                FRESULT res;
                FIL file;
                UINT bw;

                /* Mount USB */
                Debug_Print("Mounting...\r\n");
                res = f_mount(&USBHFatFS, USBHPath, 1);

                if (res == FR_OK)
                {
                    Debug_Print("Mount OK\r\n");

                    /* Create file */
                    res = f_open(&file,
                                 "0:/log.txt",
                                 FA_CREATE_ALWAYS | FA_WRITE);

                    if (res == FR_OK)
                    {
                        Debug_Print("File Opened\r\n");

                        char data[] = "Hello from STM32H750 + FreeRTOS\r\n";

                        res = f_write(&file, data, strlen(data), &bw);

                        if (res == FR_OK)
                            Debug_Print("Write OK\r\n");
                        else
                            Debug_Print("Write ERROR\r\n");

                        f_close(&file);
                        Debug_Print("File Closed\r\n");
                    }
                    else
                    {
                        Debug_Print("File Open ERROR\r\n");
                    }

                    file_written = 1;
                }
                else
                {
                    Debug_Print("Mount FAILED\r\n");
                }
            }
        }

        if (Appli_state == APPLICATION_DISCONNECT)
        {
            Debug_Print("USB Removed\r\n");
            file_written = 0;
        }
       char msg[50];
       sprintf(msg, "State: %d\r\n", hUsbHostHS.gState);
        Debug_Print(msg);

    }
}

I have tried to increase the stack size 

osThreadId_t defaultTaskHandle;
const osThreadAttr_t defaultTask_attributes = {
  .name = "defaultTask",
  .stack_size = 32768,------>increased
  .priority = (osPriority_t) osPriorityNormal,
};
/* Definitions for GUITask */
osThreadId_t GUITaskHandle;
const osThreadAttr_t GUITask_attributes = {
  .name = "GUITask",
  .stack_size = 8192 * 4,
  .priority = (osPriority_t) osPriorityNormal,
};

As soon as the mass storage is added the system goes in hardfault 
State is printed =1 (serial output)