FX Channel Select is not working DDJ 400

I have the problem that i can't select a FX anymore on Deck 2. When i'm switching the fx channel select to deck 2, i still change the fx on deck 1 but not on deck 2. However, when deck 2 is selected, i can apply an effect but it's still the effect which i selected before on Deck 1.

I'm using rekordbox 6.5.3 and a ddj 400