Studio:Incorrect type error in the New Attribute pop-up window

Hello Guys

I am using the Studio (non-subscription) with kotlin as the language to create an ENUM class, then create a new attribute in my other entity using the ENUM that I created via ‘New Attribute’ popup window. Somehow it complained an error : IncorrectOperationException: Incorrect type ‘com.xxxxxxx’(my enum class entity full name).
Has anyone experienced it before, how did you guys solve it ?
Thank you. Really appreciate if you could light up some ideas.


Can you show your source code?