It may be possible that some debris/dust is caught in the lock of your unit. Please try the following:
- Check the engraved key number and verify it matches the engraved letter on the key cylinder.
- Spray WD-40 oil in the lock.
- Tap it lightly with a hammer.
- Try the key again. If the key still does not work please contact Consumer Affairs at 1-800-323-9005 for more information.