I have an inspiron 1520 laptop. I just bought a new reachargeable battery. My old adapter wouldn’t charge it, so bought a brand new dell adapter/charger. It started charging as soon as I plugged it in, so let it charge all night to 100%. Was told to then drain the battery (by using it) till it’s dead then recharge again (doing it 3 times total). So, I used it till it died and just plugged it back in to charge, and now it won’t charge. Says the battery is performing normal, just “plugged in, but not charging.” What could have possibly happened since both were just working? I’m using it now with the adapter plugged in.