Ok, so somehow your AUTH0 byte got changed to 00 but should be E2… and you need to authenticate before you can change it. The good news is, your password is still factory default FF FF FF FF.
Ok so you already have NFC Shell. that’s good… but use carefully. Sending incorrect commands with NFC Shell can really brick your tag for real.
You’ve authenticated… good… now you need a second line after that one to change your AUTH0 byte… so your command list should look like this;
1B FF FF FF FF
A2 E3 04 00 00 E2
Then tap your tag. You need to include both lines to ensure the session remains authenticated to perform the write command.
After this you should be able to use “normal” tag writing apps again.