Attrubute can only be applied to types not declarations

Error: "Attrubute can only be applied to types not declarations" on line 2 : @unchecked

@unchecked
enum ReminderRow : Hashable, Sendable {
    case date
    case notes
    case time
    case title
    
    var imageName : String? {
        switch self {
            case .date: return "calendar.circle"
            case .notes: return "square.and.pencil"
            case .time: return "clock"
            default : return nil
        }
    }
    
    var image : UIImage? {
        guard let imageName else { return nil }
        let configuration = UIImage.SymbolConfiguration(textStyle: .headline)
        return UIImage(systemName: imageName, withConfiguration: configuration)
    }
    
    var textStyle : UIFont.TextStyle {
        switch self {
        case .title : return .headline
        default : return .subheadline
        }
    }
}