Ultralight Tags - RFID ERROR: PCD_Authenticate() failed: Timeout in communication

[thememore]

Hello,

I'm trying to learn how to write data into ultralight tags (RFID sticker tags).

I've used the examples in the MRFC522 Arduino library but I get the following error:

RFID ERROR: PCD_Authenticate() failed: Timeout in communication

I don't understand why timeout error.

I've tried to dump the info on the Serial monitor with "mfrc522.PICC_DumpMifareUltralightToSerial();" and it seems to work. I get the following output:

**Card Detected:**
 DUMP  ----------------------------------------------------------
Page    0      1      2      3
  0     04     49     E3     26
  1     7A     FC     4E     80
  2     48     48     00     00
  3     E1     10     12     00
  4     01     03     A0     0C
  5     34     03     03     D0
  6     00     00     FE     00
  7     65     6E     48     6F
  8     6C     69     51     01
  9     30     54     02     65
 10     6E     49     64     65
 11     6E     74     69     66
 12     69     65     72     3A
 13     0A     30     34     20
 14     3A     20     34     39
 15     20     3A     20     45
 END DUMP  -------------------------------------------------------
Authentication failed: Timeout in communication.
Reading failed: Timeout in communication.

I've installed the APP NFC Tools on my iPhone and it can read/write the tag with no problems.
I can also write the same tag with another APP called NFC from stanc.io.

I can write data into the tag with one app and read it with the other and viceversa. But I cannot no it with Arduino due to the Authentication time out error.

So My questions are:

1. Is the dump information all the data stored in the RFID tag? If so, why is it needed any authentication?
2. How can I manage to write on the Tag with an Arduino? Is there any way to find the Key for authenticating successfully, either in the NFC Tools APP?