Am developing an android app and I really want it to use affollested matrial dialogs specifically the theme class. When I try to import com.afollestad.materialdialogs.Theme; In this class, I get an error cannot resolve symbol theme please help this is my imports

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;