I have had two RCA tablets that do this, plugging in the AC charger doesn’t charge, I only would see the battery symbol on the tablet. I found that if I used a battery power bank and charged it from there, the battery indicator on the tablet screen would now show a percentage charged… Once it was above 5% charged, I can then switch to the AC charger and it would fully charge and operated normally. I am guessing that letting these battery completely drain is not a good thing…