Code Redemption

I bought an amazon code for the java edition of Minecraft and then proceeded to redeem the code and go to play. Only to find out that the code didn't activate the java edition for my account. When I tried to relog the code in, I was prompted with the message that the code was already in use and I couldn't activate the java edition of Minecraft. Now putting me in a frustrating loophole of trying to get java to work and also get the code to be redeemable. I just want to play java and I'm not sure why this is has to be so frustrating.