Hi, I'm a complete Blackberry newbie. I just bought a slightly used Playbook 2.0, when trying to charge it with the included travel charger nothing happens

When I plug it in, the red light comes on for a few seconds then goes out... I've left the Playbook connected to the charger for some 12 hrs now and it still hasn't booted
I've tried pushing the power button and holding it in for some seconds... no response. I need some good advice as to my options; what should I do? What are the possible solutions? It might be something obvious, 'cause I am a newbie as I stated earlier
