Weird behavior while charging - Kobo Libra 2

I have installed the latest firmware 4.38.23038 and installed the adequate patches and Nickel Menu.

I was always wondering, why my Libra 2 doesn't charge up to 100%. It gets stuck at round about 84 - 87% and stopps charging.

I have another Libra 2....it was the same....and was excactly the same firmware and patches as my other Libra 2.

Then I did a full reset of one of my Libra 2 readers.....with the result that it chages perfectly up to 100% without any issues.

Now, I consider it has to do with the tweaks and patches. Has anyoone an idea what could that be?