Problem with Hair accesory stone

I try to put Evas Circlet on Refined Devils Horns CON and dont let me with this mesage: "This items is not a valid apparience item"
I didnt understand what can be the problem...
Both are 2 slots accesory...
I use this apparience(Evas) before... in other item
So plese help me

Can some one please ake a look on this?

Same problem. Can't add eyepatch appearance to rabbit ears. Both are 1-slot accessories.