Json – Retrofit onResponse not working but onFailure can be execute

Can anyone help me? I use Log.e("CHART_RESPONSE", "sus" ); to see where it executes, and it shows in OnFailure. I’ve been trying to solve it for the past three days but it still couldn’t get it to work. Please help me.

This is API code:

public interface Api {
    @FormUrlEncoded
    @POST("register.php")
    Call<RegisterResponse> register(
            @Field("voltage") String voltage,
            @Field("current") String current,
            @Field("temp") String temp
    );
  @GET("fetch.php")
  Call<ChartResponse> init();

}

RetrofitClient code:

package com.example.apiapp;

import com.google.gson.Gson;

import okhttp3.OkHttpClient;
import okhttp3.logging.HttpLoggingInterceptor;
import retrofit2.Retrofit;
import retrofit2.converter.gson.GsonConverterFactory;

public class RetrofitClient {

    private static Retrofit retrofit = null;

    private static OkHttpClient buildClient() {
        return new OkHttpClient
                .Builder()
                .addInterceptor(new HttpLoggingInterceptor().setLevel(HttpLoggingInterceptor.Level.BODY))
                .build();
    }

    public static Retrofit getClient() {
        if (retrofit == null) {
            Gson gson=new Gson();
            retrofit = new Retrofit.Builder()
                    .client(buildClient())
                    .addConverterFactory(GsonConverterFactory.create(gson))

                    /**
                     *
                     *  base url here for api
                     */

                    .baseUrl("http://192.168.1.103/PHP-API/")
                    .build();
        }
        return retrofit;
    }
}

JSON code:

[
    {
        "voltage": [
            "110.53",
            "110.28",
            "0.00",
            "0.00",
            "0.00"
        ]
    },
    {
        "current": [
            "10.79",
            "4.93",
            "100.80",
            "0.00",
            "0.00"
        ]
    },
    {
        "temp": [
            "28.54",
            "34.00",
            "35.77",
            "0.00",
            "0.00"
        ]
    },
    {
        "hum": [
            "31.00",
            "90.13",
            "3.80",
            "0.00",
            "0.00"
        ]
    }
]

json pojo(I convert it from jsonschema2pojo):

public class ChartResponse{
    @SerializedName("voltage")
    @Expose
    private static List<String> voltage;
    @SerializedName("current")
    @Expose
    private  static List<Float> current;
    @SerializedName("temp")
    @Expose
    private  static List<Float> temp;
    @SerializedName("hum")
    @Expose
    private  static List<Float> hum;

    public static List<String> getVoltage() {
        return voltage;
    }

    public void setVoltage(List<String> voltage) {
        this.voltage = voltage;
    }

    public static List<Float> getCurrent() {
        return current;
    }

    public void setCurrent(List<Float> current) {
        this.current = current;
    }

    public static List<Float> getTemp() {
        return temp;
    }

    public void setTemp(List<Float> temp) {
        this.temp = temp;
    }

    public static List<Float> getHum() {
        return hum;
    }

    public void setHum(List<Float> hum) {
        this.hum = hum;
    }
    }

barchart code:

public class barchart extends AppCompatActivity {


    private static Object data;
    public Api api;
    private Object chartResponse;
    ArrayList<ChartResponse> chartList;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
       
        super.onCreate(savedInstanceState);
        setContentView(R.layout.barchart_main);
   
        api = RetrofitClient.getClient().create(Api.class);
        getData();
        Button Hi =findViewById(R.id.button);
        Hi.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent();
                intent.setClass(barchart.this, MainActivity.class);
                startActivity(intent);
            }
        });


    }

    /**
     * api call to get some data from server
     */


    private void getData() {

        Call<ChartResponse> call = api.init();

        call.enqueue(new Callback<ChartResponse>() {

            @Override
            public void onResponse(Call<ChartResponse> call, Response<ChartResponse> response) {
                Log.e("CHART_RESPONSE", "sus" );
                BarChart barchart = findViewById(R.id.fragment_verticalbarchart_chart);
                Log.d("CHART_RESPONSE", "success" + response.body().getVoltage());
               // ChartResponse chartresponse=response.body();
                ArrayList<Float> dataSets = new ArrayList<Float>();
                ArrayList<BarEntry> completed = new ArrayList<>();
                /**
                 *  Getting the value for Complete list
                 */
                for (int i = 0; i < 5; i++) {
                    
                   BarEntry value = new BarEntry(ChartResponse.getHum().get(i), i); 
                   completed.add(value);
                }
                for (int i = 0; i < dataSets.size(); i++) {
                    BarEntry barEntry = new BarEntry(i, dataSets.get(i));
                    completed.add(barEntry);
                }
                BarDataSet barDataSet = new BarDataSet(completed, "Completed Issue");
                /**
                 *  Add complete data into the bar chart
                 */
                barDataSet.setColor(Color.rgb(0, 155, 0));
                BarData data = new BarData(barDataSet);
                barchart.setData(data);
                barchart.invalidate();
                barchart.setData(data);
                barchart.invalidate();



            }

           @Override
            public void onFailure(Call<ChartResponse>call, Throwable t) {
               Log.e("CHART_RESPONSE", "sfs" );
            }
        });

    }
}

I’ve added:

    implementation 'com.github.PhilJay:MPAndroidChart:v3.1.0'
    implementation 'com.google.code.gson:gson:2.6.2'
    implementation 'com.squareup.retrofit2:retrofit:2.0.2'
    implementation 'com.squareup.retrofit2:converter-gson:2.0.2'
    implementation 'com.squareup.okhttp3:okhttp:3.2.0'
    implementation 'com.squareup.okhttp3:logging-interceptor:3.6.0'

and in manifest:
android:usesCleartextTraffic="true"