Please help how do I get my tablet pen to work??

Ok so I broke my stylus pen for my gateway tablet so I bought a new one off ebay however it isn't working and I want to check to see if there's something I can do before I return it important link. I know it's charged because the computer seems to detect it, the thing is the second I touch the pen to the screen the mouse disappears and I can't write or anything with it, however like I said I think it is detecting it because the mouse disappears. What can I do?

Thanks