Atmega 32u4 bootloader error Device signature

Hello to all,
First, apologize my english, I'm french, but I expect you will understand my problem and give me some help :slight_smile:

I start a arduino project with a PN532 NFC reader:

I make them from china and some of them had a bad programming and now I get this error when I retry to program it with an arduino uno 328 as isp:

avrdude: Device signature = 0xffffff
avrdude: Yikes! Invalid device signature.
avrdude: Expected signature for ATmega32U4 is 1E 95 87

I see it look like a fuse problem and I need to write them but I don't have any idea how you can do that and don't really understand some topics (Noob spotted)

I expect you can do something for me :slight_smile:

0xffffff usually means bad wiring or a completely dead chip...

Wiring work with another board...
I will check if there is no hardware problem, there are no way to re set the orginal configuration? :confused:

Okay, some news, both PCB have a hardware problem (bad soldering).
Now they both send me 0x000000, can I expect something?