SOMEONE PLEASE HELP ME?!

Hi good evening,

i have currently purchased a laptop from 'the good guys' merchant and have bought my anti-virus norton from them,

I've had to re-format my computer due to system problems.

My antivirus was purchased for 3 years and have not even exceeded 6 months but it won't let me re-install due to having it installed previously.

It say's the only way is to buy a key or re-new.

I refuse to pay due to that fact that i have already paid for the goods.

Please help me? thanks :)

It really is inconvenient that norton is a big antivirus company and there are no online helpers...