FX7500 embedded Get MACAddress return false

How to get MAC address info from embedded c?

Code:

void SystemInfo()
{
RFID_HANDLE32 readerManagementHandle;
RFID_STATUS rfidStatus = RFID_API_SUCCESS;
LOGIN_INFO loginInfo;
READER_TYPE readerType = FX;
BOOLEAN secureMode=0;
READER_SYSTEM_INFO SystemInfo;

wcscpy(loginInfo.userName, L"admin");
wcscpy(loginInfo.password, L"change");
wcscpy(loginInfo.hostName, L"localhost");

loginInfo.forceLogin = true;
loginInfo.version = RFID_API3_5_1;

if(RFID_API_SUCCESS == RFID_Login(&readerManagementHandle, &loginInfo, readerType, secureMode, NULL))
{
  rfidStatus = RFID_GetSystemInfo(readerManagementHandle, &SystemInfo);

  wprintf(L"\nFirmware: %ls",SystemInfo.radioFirmwareVersion);
  wprintf(L"\nSN: %ls",SystemInfo.serialNumber);
  wprintf(L"\nMAC: %ls",SystemInfo.networkInfo->MACAddress);

  RFID_Logout(readerManagementHandle); // Logout so that Dll is cleaned up
}
}

resule:

Firmware: 2.7.19

SN: XXXXXXXXXXX(mark)

MAC: false