These codes usually come on an A5 paper with a big red triangle in the corner that says Don’t throw away!
If you didn’t get that, I think the retailer is who you should speak to as they didn’t sell you what you paid for. I can see how that’s difficult if you bought it abroad though.
Good luck with retrieving your code! The procedures for registration may be a bit convoluted, but the software is worth it in my opinion 
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