Another thing to watch out for with that particular reader is short in length positive pin on delivery device or flush or inset positive pin. Do not use with a direct to battery / pseudo / fake hybrid type delivery device.
It will create flaky inaccurate readings up to dead short, on that one protections may not actually work when shorted.
Must be a low quality clone, should use flat top, unless you've stuffed a button top in it jacking up the battery contacts.
I was told it only took button top.
This may explain my issues with the "non" message 70% of the time when I test my stm RBAs