Topic: Something very strange


First, sorry for my bad english because I'm french.

I made a clone of an NFC mifare Cmlaissk 1K tag that I use to open my garage door.
I clone it (including the UID) on a "magic" changeable UID Mifare tag.

Everything worked fine during more than 2 years.
This morning the original tag works perfectly, but the cloned one does'nt work anymore.

I've tried with other clone tags that worked great before, same thing...

Do you have an idea regarding why, from one day, to the other, after  more than 2years working fine, thoses tags are not recognized ?

Thanks a lot for your help.

Kinds Regards