问转换json对象时找不到类型转换器？

EN

import androidx.room.TypeConverter
import com.animsh.itunessearch.models.ITunesResponse
import com.google.gson.Gson
import com.google.gson.reflect.TypeToken


class ResultTypeConverter {

    var gson = Gson()

    @TypeConverter
    fun responseToString(Response: Response): String {
        return gson.toJson(Response)
    }

    @TypeConverter
    fun stringToResponse(data: String): Response {
        val listType = object : TypeToken<Response>() {}.type
        return gson.fromJson(data, listType)
    }
}