activation I need some help

I have purchased Norton Internet Security 2010 in oct 3, 2010 and installed onto one computer. I am now attempting to install it another computer. When I enter the code it pops up as  Invalid subscription renewal code this subscription renewal code has already been used the maximum number of times allowed . I only thing is a only used it once on one computer. I then go to the stupid  virtual helper NATHAN!!! who tells me to logo on to my Norton Account which I do so that I can see how many remaining activation I have. The only thing that is located in the "protection for block is " -" . It doesn't say anything or tell how many activation are left. I am stuck and need some help since Norton doesn't seem to have real help that you don't have to pay for.......

 

 

Please help I am so stressed and I can't seem to get any from the website