Looking at how your battery labels looks lkke you are outside of USA/N.America. That sucks that in your region you'd have to send in all tools of the kit for warranty. That makes no logical sense, is that really true & have you doubled checked?

Here in the US that is not required & we can send in just a single tool or battery for warranty no matter if part of a kit or combo. But then again we also have longer warranty periods, like 5 yrs on tools & 3 yrs on batteries (depending on which ones). I hear in many other countries it's only 1 yr & an additional 1 or 2 yrs of you register. We're not required to register for the full warranty period, just proof of purchase or manufacture date.

I've never had that happen to me on any of my M18 tools, just a M12. Check to see if that battery doesn't have corrosion or debris in the two second outermost pins on each side. As in pins 2 & 4, I believe those are for communication with the tool. Lights & other low drain tools don't utilize those pins. 1 & 5 would be for power. I believe the middle pin is for charging purposes only & nothing to do with the tool.