My tablet has stopped charging even though I plug it in. I have tried a different charger, and different wall outlets,...

This may be several issues. The problem may be either a bad motherboard, a faulty display, or a bad battery. Refer to the troubleshooting page for each. Try one, and try to power it on. If that still doesn't fix the issue, try the other and try to power on again. Note: if you replace the battery, make sure to charge it.