Caching is not working in Android Paging 3

I have implemented application using codelabs tutorial for new Paging 3 library, which was release week ago. The problem is application is not working in offline mode. It does not retrieve data from Room database.

Tutorial Repo link :- https://github.com/googlecodelabs/android-paging

Code:-

1. RepoDao.kt

   @Dao
   interface RepoDao {
   
      @Insert(onConflict = OnConflictStrategy.REPLACE)
      suspend fun insertAll(repos: List<Repo>)
   
      @Query("SELECT * FROM repos WHERE " +
       "name LIKE :queryString OR description LIKE :queryString " +
       "ORDER BY stars DESC, name ASC")
      fun reposByName(queryString: String): PagingSource<Int, Repo>
   
      @Query("DELETE FROM repos")
      suspend fun clearRepos()
   }
   

2. GithubRepository.kt

   class GithubRepository(
       private val service: GithubService,
       private val database: RepoDatabase
   ) {
      fun getSearchResultStream(query: String): Flow<PagingData<Repo>> {
   
         val dbQuery = "%${query.replace(' ', '%')}%"
         val pagingSourceFactory = { database.reposDao().reposByName(dbQuery) }
   
         return Pager(
            config = PagingConfig(pageSize = NETWORK_PAGE_SIZE),
            remoteMediator = GithubRemoteMediator(
                   query,
                   service,
                   database
           ),
           pagingSourceFactory = pagingSourceFactory
         ).flow
      }
   
      companion object {
          private const val NETWORK_PAGE_SIZE = 50
      }
   }
   

3. SearchRepositoriesViewModel.kt

   @ExperimentalCoroutinesApi
   class SearchRepositoriesViewModel(private val repository: GithubRepository) : ViewModel() {
       private var currentQueryValue: String? = null
   
       private var currentSearchResult: Flow<PagingData<Repo>>? = null
   
       fun searchRepo(queryString: String): Flow<PagingData<Repo>> {
           val lastResult = currentSearchResult
           if (queryString == currentQueryValue && lastResult != null) {
               return lastResult
           } 
           currentQueryValue = queryString
           val newResult: Flow<PagingData<Repo>> = repository.getSearchResultStream(queryString).cachedIn(viewModelScope)
           currentSearchResult = newResult
           return newResult
       }
   
   } 
   

4. SearchRepositoriesActivity.kt

   @ExperimentalCoroutinesApi
   class SearchRepositoriesActivity : AppCompatActivity() {
   
       .....
       private lateinit var viewModel: SearchRepositoriesViewModel
       private val adapter = ReposAdapter()
   
       private var searchJob: Job? = null
   
       // this is where adapter get flow data from viewModel
       // initially this is called with **Android** as a query
       private fun search(query: String) {
           searchJob?.cancel()
           searchJob = lifecycleScope.launch {
               viewModel.searchRepo(query).collectLatest {
                   adapter.submitData(it)
               }
           }
       }
       .....
    }
   

Output:- It is just showing the empty recyclerview when application is open in offline mode.