Android. Ошибка Unable to start activity. Что делать?

Никита Савченко,

package mate.files;

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Typeface;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;

import java.util.Locale;
import java.util.concurrent.TimeUnit;

public class Welcome extends AppCompatActivity {

    //Counter for Spinner's Listener
    int Counter = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_welcome);
        getSupportActionBar().hide();
        //Title Font
        TextView textView = (TextView) findViewById(R.id.WelcomeTitle);
        Typeface typeFace = Typeface.createFromAsset(getAssets(), "Title.ttf");
        textView.setTypeface(typeFace);
        //Button Font
        Button button = (Button) findViewById(R.id.nextButton);
        button.setTypeface(typeFace);

        //Lang Spinner
        Spinner Lang = (Spinner) findViewById(R.id.Lang);
        ArrayAdapter<?> Adapter = ArrayAdapter.createFromResource(this, R.array.Langs, R.layout.my_spinner);
        Adapter.setDropDownViewResource(R.layout.my_spinner_dropdn);
        Lang.setAdapter(Adapter);

        Locale CurLang = this.getResources().getConfiguration().getLocales().get(0);
        Resources res = this.getResources();
        android.content.res.Configuration conf = res.getConfiguration();
        if (CurLang.toString().equals("en_US")) {
            Lang.setSelection(0);
        }
        if (CurLang.toString().equals("ru_RU")) {
            Lang.setSelection(1);
        }

        AdapterView.OnItemSelectedListener itemSelectedListener = new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                if (Counter == 0) {
                switch (position) {
                    default:
                        break;
                    case 0:
                        conf.setLocale(new Locale("en_US"));
                        break;
                    case 1:
                        conf.setLocale(new Locale("ru_RU"));
                        break;
                }
                getBaseContext().getResources().updateConfiguration(conf, null);
                try {
                    TimeUnit.SECONDS.sleep(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                Intent intent = new Intent(getBaseContext(), MainActivity.class);
                startActivity(intent);
            }
                }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
            }
        };
        Lang.setOnItemSelectedListener(itemSelectedListener);
    }
    public void GetStartedClicked(View view) {
        Intent intent = new Intent(this, WelcomeAccount.class);
        startActivity(intent);
    }

     public void LangClicked(View view)
     {
        Counter = 1;
     }
}