requesting mixcraft 5

I had mixcraft 5 and I registered it with the key that I found and i worked for a while but now when I open mixcraft it wants me to register again and Ill put the same key in again and it says its registered but I cant save a song because itll still say I need to register it and same for when I close and reopen mixcraft.So I use Mixcraft 4.1 which doesnt need a key because it has to do with a cracked exe file or something but Im requesting a cracked mixcraft 5 and Ive already used the TEAM AIR code.