Free bedrock code

A while back, if you had Minecraft before Microsoft bought Mojang. You were given a code to get a free copy of Minecraft windows 10 edition. But when I clicked on it, nothing happened. I didn't care at the time, because my computer couldn't run Minecraft that well anyway. but now I have no way to access my Minecraft windows 10 edition code. I could never even redeem it in the first place. i was wondering if i can access my old code, or possibly get a new one?