Error caused by creating a viewmodel using Dao database

Question

I try to use dao database in my app and I get this error when i try to create a view model:

E/libc: Access denied finding property "ro.vendor.df.effect.conflict" E/Perf: Fail to get file list com.example.kiedyssieuda E/Perf: getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array E/Perf: Fail to get file list com.example.kiedyssieuda getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array

Person class:

@Entity(tableName = "people_table")
data class Person(var name: String,
                  var surname: String ){
    @PrimaryKey(autoGenerate = true)
    var user_id: Int = 0
}

PeopleDao interface

@Dao
interface PeopleDao {
    @Insert
    fun insert(person: Person)

    @Update
    fun update(person: Person)

    @Delete
    fun delete(person: Person)

    @Query("SELECT * FROM people_table")
    fun getAllPeople(): LiveData<List<Person>>

    @Query("DELETE FROM people_table")
    fun deleteAllRows()
}

PeopleDatabase abstract class

@Database(entities = [Person::class], version = 1, exportSchema = false)
abstract class PeopleDatabase : RoomDatabase(){

    abstract fun peopleDao(): PeopleDao

    companion object{
        private var instance: PeopleDatabase? =null

        fun getInstance(context: Context): PeopleDatabase?{
            if (instance==null){
                instance = Room.databaseBuilder(
                    context,
                    PeopleDatabase::class.java,
                    "people_table")
                    .fallbackToDestructiveMigration()
                    .build()
            }
            return instance
        }
        fun deleteInstanceOfDatabase(){
            instance=null
        }
    }
}

PeopleRepository class

class PeopleRepository(application: Application) {
    private var peopleDao: PeopleDao
    init {
        val database:PeopleDatabase? = PeopleDatabase
            .getInstance(application.applicationContext)

        peopleDao = database!!.peopleDao()
    }
    fun insertPerson (person: Person): Job =
        CoroutineScope(Dispatchers.IO).launch {
            peopleDao.insert(person)
        }
    fun uptadePerson (person: Person): Job =
        CoroutineScope(Dispatchers.IO).launch {
            peopleDao.update(person)
        }
    fun deletePerson(person: Person): Job =
        CoroutineScope(Dispatchers.IO).launch {
            peopleDao.delete(person)
        }
    fun getAllPeopleAsync(): Deferred<LiveData<List<Person>>> =
        CoroutineScope(Dispatchers.IO).async {
            peopleDao.getAllPeople()
        }
    fun deleteAllRows(): Job =
        CoroutineScope(Dispatchers.IO).launch {
            peopleDao.deleteAllRows()
        }

PeopleViewModel class

class PeopleViewModel(application: Application):
    AndroidViewModel(application) {

    private var peopleRepository: PeopleRepository =
        PeopleRepository(application)

    private var allPeople: Deferred<LiveData<List<Person>>> =
        peopleRepository.getAllPeopleAsync()

    fun insertPerson(person: Person){
        peopleRepository.insertPerson(person)
    }
    fun uptadePerson(person: Person){
        peopleRepository.uptadePerson(person)
    }
    fun deletePerson(person: Person){
        peopleRepository.deletePerson(person)
    }
    fun getAllPeople(): LiveData<List<Person>> = runBlocking {
        allPeople.await()
    }
    fun deleteAllRows(){
        peopleRepository.deleteAllRows()
    }
}

MainActivity:

class MainActivity : AppCompatActivity() {
    private lateinit var viewModel: PeopleViewModel

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val users = ArrayList<Person>()
        //users.add(Person("abc","123"))

           viewModel = ViewModelProvider
               .AndroidViewModelFactory
               .getInstance(application)
               .create(PeopleViewModel::class.java)
    }
}