RetrofitSetup.java

 private Retrofit getRetrofit() {
  
        if(retrofitInstance != null) return retrofitInstance;
  
        HttpLoggingInterceptor logging = new HttpLoggingInterceptor();
        logging.level(HttpLoggingInterceptor.Level.BODY);

        OkHttpClient okHttpClient = new OkHttpClient.Builder()
                .addInterceptor(logging)
                .build();

        retrofitInstance = new Retrofit.Builder()
                .baseUrl(BuildConfig.BASE_URL)
                .client(okHttpClient)
                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                .addConverterFactory(GsonConverterFactory.create())
                .build();
  
        return retrofitInstance;
   
    }