Olight Universal Charger Repulsed by Battery?!?

So I’ve got the Olight universal charger that attaches to the battery poles by magnets. It has seemed to work well. Then I tried to charge a 21700 and instead of attraction, the magnetic attachment was repulsed by the battery. It would not stick to one of the ends of the battery and could not charge as a result.

The writing on the gray cell says:

NCA 21700T

  • 3.7V ZS50T -
    20.49.1156989

It came with one of my Convoy lights. I never had this happen before. Anyone know what’s up?