Minecraft launcher does not work - after activating code, I still have only demo version

Hi,

I have problem with my launcher. I bouth minecraft and received code. After activating code and downloading instalation pack, I still have only demo version in my launcher or possibility to buy the minecraft. 

Unfortunaltelly the code is no longer valid, since it could be used only once. please let me know who can I activate full version of minecraft in my launcher?