nfc-mfclassic does not allow writing on a tag

Trying to copy an NFC tag. I did it some years ago without difficulties but did not manage to do it again. I think that the problem comes from this command:

-sh
nfc-mfclassic W a net-security.dmp

which is not writing on the tag. Here are more informations (NB: I put some * for the UID and for the key). * First I read the tag I want to copy:

-shellsession
    $ nfc-list -v

    nfc-list uses libnfc 1.8.0
    NFC device: ACS / ACR122U PICC Interface opened
    1 ISO14443A passive target(s) found:
    ISO/IEC 14443A (106 kbps) target:
        ATQA (SENS_RES): 00  04  
    * UID size: single
    * bit frame anticollision supported
          UID (NFCID1): * * * *  				
         SAK (SEL_RES): 08  
    * Not compliant with ISO/IEC 14443-4
    * Not compliant with ISO/IEC 18092
    
    Fingerprinting based on MIFARE type Identification Procedure:
     * MIFARE Classic 1K
     * MIFARE Plus (4 Byte UID or 4 Byte RID) 2K, Security level 1
     * SmartMX with MIFARE 1K emulation

* then I made a dump of the tag (the key is in the file extended-std.keys):

-shellsession
    $ mfoc -f extended-std.keys -O net-security.dmp

* then I copy the dump on a blank tag:

-shellsession
    $ nfc-mfclassic W a U**** net-security.dmp

    Attempting to use specific UID: 0x2e 0x9f 0xd7 0xa0
    NFC reader: ACS / ACR122U PICC Interface opened
    Found MIFARE Classic card:
    ISO/IEC 14443A (106 kbps) target:
        ATQA (SENS_RES): 00  04  
           UID (NFCID1): * * * *  
          SAK (SEL_RES): 08  
    RATS support: no
    Guessing size: seems to be a 1024-byte card
    Sent bits:     50  00  57  cd  
    Sent bits:     40 (7 bits)
    Received bits: a (4 bits)
    Sent bits:     43  
    Received bits: 0a  
    Card unlocked
    Writing 64 blocks |................................................................|
    Done, 64 of 64 blocks written.

All seems ok but the copy of the tag is not working. * Just to see, I made a dump of the copy of the tag.

-shellsession
    $ mfoc -f extended-std.keys -O net-security_copy.dmp
    
    The custom key 0x**** has been added to the default keys
    Found Mifare Classic 1k tag
    ISO/IEC 14443A (106 kbps) target:
        ATQA (SENS_RES): 00  04  
    * UID size: single
    * bit frame anticollision supported
           UID (NFCID1): * * * * 
          SAK (SEL_RES): 08  
    * Not compliant with ISO/IEC 14443-4
    * Not compliant with ISO/IEC 18092
    
    Fingerprinting based on MIFARE type Identification Procedure:
    * MIFARE Classic 1K
    * MIFARE Plus (4 Byte UID or 4 Byte RID) 2K, Security level 1
    * SmartMX with MIFARE 1K emulation
    Other possible matches based on ATQA & SAK values:
    
    Try to authenticate to all sectors with default keys...
    Symbols: '.' no key found, '/' A key found, '\' B key found, 'x' both keys found
    (swip)
    Sector 00 - Found   Key A: ****         Found   Key B: ****
    Sector 01 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 02 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 03 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 04 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 05 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 06 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 07 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 08 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 09 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 10 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 11 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 12 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 13 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 14 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff
    Sector 15 - Found   Key A: ffffffffffff Found   Key B: ffffffffffff

The key is ok only for the sector 0. The dump for the copy of the tag is different of the original tag. I think that during the copy, there is a problem but I don't know which. If someone has an idea....