All Vitamins stopped having effect in my Dragonite (White 2). Does that mean he can´t receive more EVs? And when I try to train them in join avenue´s fitness they say he´s too strong already. WHAT'S GOING ON!?
His EVs are maxed out. Simple as that.
Yep, if you want to confirm this call bianca and she will say your Pokemon has worked really hard. She also says when a stat has reached 252 evs.