I just picked up a playbook for the first time and during the setup it says "Battery Level Critically Low, Please connect your tablet to a power source. (which I have done using the wall charger that came with the playbook) and it says setup will resume when the battery gets to 20%, but it doesnt seem to by charging at all. Its at 0% still and its been 30mins. Am I doing something wrong? Anyone else have this issue and how to get around it?