RC522 not working - How to search issue hardware


I'm working on a RFID project. I have two RC522 sensor and two UID tags.
So I have :

  • Sensor RC522 n°1
  • Sensor RC522 n°2
  • UID tag n°1
  • UID tag n°2

I practiced in a first time only on the sensor RC522 n°1 which was doing its job, it detects the both tags very well.

I didn't change any wire, and only replaced sensor RC522 n°1 by sensor RC522 n°2. All seem OK, the red led is lighting so I try to detect my tags and then... Nothing, this sensor doesn't detect both tags.

It is the same provider. I don't understand what is going wrong.

How can I control the hardware ? How can I find the origin of the problem ?

Thank you if you can help me ! :slight_smile: