I contacted live chat for the solution. but it seems that there is something wrong with Symantec server, therefore, live chat customer service could not solve my problem, but she will call me back after the issue is solved.
I am writing here for checking if anyone has the same problem as I do.
I purchased NIS 2012 upgrade earilier on Symantec online shop, which means I have a new product key. My exist subsciption of NIS 2011 still has 214days left, but, after install 2012, 2012 did not grab the exist data! NIS 2012 uses my new product key, 366Days left. I tested it on my 2ed PC, and the result is the same, NIS 2012 uses my new product key.
And more, what is interesting is, I uninstalled NIS 2012, and re-installed NIS 2011, the subsciption show the correct data, my old subsciption is back!! OK! I think I have wasted 2 out of 3PCs spots. I hope the customer service can solve this probem, give my new product key back to unactivated status, and correct the record after upgrading to NIS 2012, I am still waiting for her call.