NIS Installation after system re-install

Hello, I am sure this is a often asked question, so here's to hoping for a speedy and succinct answer.

Recently I upgraded my PC's primary harddrive to a SSD to boost performance. I now find that I cannot download or install Norton Internet Security as your website keeps flagging up 'Norton Internet Security has no remaining installs'. I understand from other threads that such a hardware change can cause Norton to assume this is a new machine, however I can ensure you it is not. I have all of the product keys at the ready, purchase confirmation too and atleast 6month of paid service remaining (according to the website). 

How do I get around this issue, download/install my package and resume my service?