Dewalt Battery Not Fully Charged - Only Up To Two Bars

How I fixed my dewaly 20v not able to fully charge issue.
The dewalt charger was showing solid red light which means the battery is fully charged in normal case.
However, when I pressed the battery indicator, it only charged up to 2 bars, which means the battery is not fully charged.
The dewalt charger stop charging when the battery still not fully charged yet.
To fix this, I connected the B+ terminal of the bad battery to another B+ terminal of a healthy battery.
Then connect B- terminal to B- terminal.
Let it stay connected for around 15 seconds.
After that, disconnect it and put the battery to charge again on the charger.
The battery should be able to fully charge now and up to 3 bars.

[@ElCaminoGrill-Market]

That did not work.