Pokemon Platinum help: The lady in Floaroma won't give me the Gracidea flower!?

I really want a sky form shaymin, and the lady in floroma won't give me the flower. I have a national pokedex and a shaymin, which I got through the pokemon modifier action replay. I know you can get the flower if shaymin is hacked, but it has to be a fateful encounter, and I don't know what that is. . . I talked to the lady during the day time, and no, I did not get my shaymin at flower paradise, I used the modifier. I did not defeat the elite four, I just have the national dex. I would love some help shaymin is my favorite pokemon =D