Pokemon Platinum's Event Key Items don't work.

[Yepi69]

I missed the events long time ago so, i used a cheat code to get the Azure Flute and the Member card to get both Arceus and Darkrai, the problem is both key items don't work, the member card doesn't open the Inn door and the Azure Flute doesn't work either (doesn't show me the message to use it and yes i tried on the Spear Pillar after getting Dialga and Palkia) i have received both of the key items by the PokeMart guy.

Why it isn't working?