I have 125kHz tags and cards. I cannot write then using Flipper zero.
I am sure that those tags and cards are writable, because I have my RFID reader/writer bought on Ali Express:
And with this device I can write on the tags and cards.
on Flipper those cards are recognised as EM4100.
is the writer really working ? I received Flipper Zero few weeks ago and I upgrade it to the last firmware.
Many thanks for your support