I've been struggling with setting up variations on my site, but I have hundreds of possible variations...so I'd be happy to rest my brain a little bit and try to help you with your issue. Maybe it will give me ideas on how to fix mine.
First you should click on the attributes option in your WP admin sidebar. Follow the on screen instructions to add new attributes to set-up the following attributes: Country and Length of Subscription.
After those are created you can view a list of the attributes and there should be an option to "Configure Terms." Click on Configure Terms for Country and add the following: US, Canada, INTL. Save. Then "Configure Terms" for the length of subscription as follows: One Year, Two Year, Three Year. Save.
Now go back to your product list (by clicking "products" on the sidebar) and click Edit to edit the specific product that will need these variations. On the product editing page scroll down to the Product Data interface and open the attributes tab. From here you need to select the attributes that will apply to this product. Now click on the Save Draft button.
Scroll back down to the Product Data interface and change the product type to "Variable Product," then open the "Variations" tab. Then click the button to "Link All Variations." Now, one by one open the toggle for each variation and enter data for that specific combo of variables (you will probably only need to give the price info). Information like shipping, dimensions, or tax can be inherited from the parent product (controlled by settings you choose in the other tabs in the Product Data section).
I hope that answers your question! If not, let me know what happens.