The shift codes have an expiry, and when they expire, they may not work. However, in many instances, we have seen that even when the code is not expired, it doesn’t work. This issue may arise even if the Shift code is bugged because of glitches in the Borderlands or Shift websites. There could be more problems, such as individual code errors with your account and missing golden keys from the inventory. If you keep running into these problems, you can search the knowledge base for a solution or open a help case with 2K Games. When you submit a support ticket, be sure to clearly and concisely describe the issue so that it may be resolved quickly.