Xbox Live subscription not working?

I got a 12 month Xbox Live code last December. I did not want to enter the code at first because I still had Xbox Gold until yesterday, but then I had entered the code and everything worked normally. Normally the subscription would have to be extended after the previous one expired but it is not with me. Now I have no idea what I can do because I don't want to buy 12 months again. My question is whether someone can help me with this or someone has had such an experience and what he did about it?

Try redeeming the code again and if that doesn't work, contact support

Ask the support