As you don't have an original Arduino please check if the 3V3 provides enough power for the MFRC522. The chip may draw up to 100mA. The original UNO supplies up to 150mA on 3V3, so check your's.
As you don't have an original Arduino please check if the 3V3 provides enough power for the MFRC522. The chip may draw up to 100mA. The original UNO supplies up to 150mA on 3V3, so check your's.