我正在尝试使用View/ViewModel/UseCase/Repository模式进行基本的网络调用。主异步调用通过协程执行，两者都是使用Dispatchers.IO启动的。

首先，以下是相关代码：

ViewModel：

class ContactHistoryViewModel @Inject constructor(private val useCase: GetContactHistory) : BaseViewModel() {
    // ...
    fun getContactHistory(userId: Long, contactId: Long) {
        useCase(GetContactHistory.Params(userId, contactId)) { it.either(::onFailure, ::onSuccess) }
    }
}

GetContactHistory用例：

class GetContactHistory @Inject constructor(private val repository: ContactRepository) : UseCase<ContactHistory, GetContactHistory.Params>() {

    override suspend fun run(params: Params) = repository.getContactHistory(params.userId, params.contactId)
    data class Params(val userId: Long, val contactId: Long)
}

上面使用的基础UseCase类：

abstract class UseCase<out Type, in Params> where Type : Any {

    abstract suspend fun run(params: Params): Either<Failure, Type>

    operator fun invoke(params: Params, onResult: (Either<Failure, Type>) -> Unit = {}) {
        val job = GlobalScope.async(Dispatchers.IO) { run(params) }
        GlobalScope.launch(Dispatchers.IO) { onResult(job.await()) }
    }
}

最后是仓库：

class ContactDataRepository(...) : SyncableDataRepository<ContactDetailDomainModel>(cloudStore.get(), localStore),
        ContactRepository {

    override fun getContactHistory(userId: Long, contactId: Long): Either<Failure, ContactHistory> {
        return request(cloudStore.get().getContactHistory(userId, contactId), {it}, ContactHistory(null, null))
    }

    /**
     * Executes the request.
     * @param call the API call to execute.
     * @param transform a function to transform the response.
     * @param default the value returned by default.
     */
    private fun <T, R> request(call: Call<T>, transform: (T) -> R, default: T): Either<Failure, R> {
        return try {
            val response = call.execute()
            when (response.isSuccessful) {
                true -> Either.Right(transform((response.body() ?: default)))
                false -> Either.Left(Failure.GenericFailure())
            }
        } catch (exception: Throwable) {
            Either.Left(Failure.GenericFailure())
        }
    }
}

**摘要：**在存储库中的catch{}块中放置调试断点(如上图所示)，表明正在抛出android.os.NetworkOnMainThreadException。这很奇怪，因为这两个协程都是在Dispatchers.IO的上下文中启动的，而不是Dispatchers.Main(Android的主用户界面线程)。

**问题：**为什么会抛出上述异常，如何纠正此代码？