           // Starting of a new sector ... try to to authenticate
           Serial.print("------------------------Sector ");Serial.print(currentblock/4, DEC);Serial.println("-------------------------");
            Serial.print("keys used:");
-           for (uint8_t i = 0; i < 5; i++)
+           for (uint8_t i = 0; i < 6; i++)
            {
             Serial.print(" ");Serial.print(KeyA_List_D3[currentblock/4][i], HEX);
            }


byte KeyA_List_D3[][6] =
{
  { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },  // Sector 0
  { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },  // Sector 1
  { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },  // Sector 2
  { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },  // Sector 3

           
          if (currentblock == 0)
          {
              success = nfc.mifareclassic_AuthenticateBlock (uid, uidLength, currentblock, 0, KeyA_List_D3[0]);
              
          }
          else
          {
              success = nfc.mifareclassic_AuthenticateBlock (uid, uidLength, currentblock, 0, KeyA_List_D3[currentblock/4]);
          }
          if (success)
          {
