“Can not save key file” Error when trying to write onto NFC

Everytime I try to write a simple text file from NFC tools on ios it produces this error message. What am I doing wrong?

I had a similar error doing a different task. I held down the power button until the Flipper turned off. Then I powered it back on. A reboot is the answer to many issues.

hi, did you ever get a solution for this error, i have same issue while reading nfc v card.