What's going on with my NIS license?...

I just found a strange occurrence with my NIS license. I have a 1-year, 3-user license installed in 3 laptops. One of the laptops listed in my Norton Account, for some reason unbeknownst to me, shows a "trial" license, even though I entered a license key to it and the expiration date in this machine's Norton UI correctly indicates 134 days remaining for expiration.

My other two laptops appear under their correct names and don't show any visible issue. The license key is shown as having been correctly applied to them.

Strangely, one fourth laptop appears now identified as "[MyName]-Windows 7".  I can't make sense of what it may be or where it may have come from, as I only have 3 laptops!... This fourth laptop only showed up after I installed Norton's update 22.5.2.15 yesterday. 

Before yesterday, all my 3 laptops (and only my 3 laptops) appeared listed in my Norton Account under their proper names: T61p, T510 and W530. The only issue till now was the fact that the T61p showed my subscription as a "Trial" but I never bothered much about this, because in the machine itself, the proper number of days remaining for the end of the subscription always appeared correctly stated.

Now, with this "new arrival", I can see that the license key is applied to it too, which apparently justifies the fact that Norton has shown all along that all my three installs were exhausted and I always took this as meaning my real three computers! But what on earth is this "[MyName]-Windows 7" device coming from? In how many devices is my license actually installed? 

Does anyone have any explanation for this?

Thanks for help.