Why can't I install power armor mods?

I can't install any mods on my X-01 power armor in Fallout 76, although I bought them from the dealer there. The mods are even displayed to me, but if I press X (PS4) to install Does not happen. Does anyone have an idea what I can do?

As far as I know, you also need the appropriate perk cards to make appropriate height modifications. They have to be equipped.

Got everything, seems to be a bug

Sure that they are the correct mods? The X01 mods are quite rare sown and also have the corresponding type designation before. It must be called in the description "X01-ExplosiveVentMod" to give an example.

Did you buy the mod or the blueprint? Most dealers have yes the blueprints for something. Go with the Pip-Boy in the notes, then there would have to be "Bauplan xyz", use the note. And you also need the material to build that at the Power Armor Workbench.