How is the premium subscription linked to a PC?

So, following scenario: Two months ago, I tried AVG premium, the free trial. Yesterday, I saw the Email that my subscription would get renewed in 4 days. So i tried to cancel it. But there was a problem: I wasnt logged in on the AVG on my computer when I made that subscription. I have an AVG account, running under a different Email adress than this one, and I had that one since I used this program, but thesubscription wasnt linked to this account. So I had no account with which i could cancel the auto renewal with. Then i realised that the reminder Email was send to this Email adress I'm currently using, but I had no account with this adress. I tried to import the subscription to my previous account by adding it via the activation code, but it still didnt show up under my subscriptions. So I made an ENTIRELY NEW account with the adress the reminder got send to, and low and behold, theres the subscription! How is this possible? how can a subscription be linked to an account I just created? If there already had been an account with my current adress, I imagine it would have told me, something like "This Email adress is already registered". Can someone explain this to me?

Hi Noah,

We will help you with the subscription.
When you originally subscribe for AVG product, you need to enter email address and card details.
The AVG subscription will be automatically registered under this email address even if you haven't created My Account under this email address.
To view the subscription, you need to create a new My Account under the registered email address.
We would also like to confirm that the auto-renewal for your subscription is already cancelled.
The license will not be renewed and no money will be taken from your account.
Let us know if you have further queries.

Hi Noah,

We will help you with the subscription.
When you originally subscribe for AVG product, you need to enter email address and card details.
The AVG subscription will be automatically registered under this email address even if you haven't created My Account under this email address.
To view the subscription, you need to create a new My Account under the registered email address.
We would also like to confirm that the auto-renewal for your subscription is already cancelled.
The license will not be renewed and no money will be taken from your account.
Let us know if you have further queries.