retrofit return a null body in release

Question

i used retrofit to call the api and it work fine in debug but when i create a release apk it crash with null pointer Exception i can't know why in the release

here is the log file in the release apk

2020-05-28 10:29:37.680 7935-7935/com.sideeg.afia_user E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.sideeg.afia_user, PID: 7935
java.lang.NullPointerException: throw with null exception
    at com.sideeg.afia_user.activates.LoginActivity$b.a(:84)
    at i.i$b$a.a(:82)
    at i.a.run(Unknown Source:6)
    at android.os.Handler.handleCallback(Handler.java:790)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6494)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

this the api declare

@FormUrlEncoded
@POST("api/users/login")
Call<LoginResponse> register(@Field("name") String name, @Field("phone") String mobile);

this the Login Model

public class LoginResponse {

@SerializedName("data")
private LoginData data;

@SerializedName("error")
private Boolean error;

@SerializedName("message")
private String message;

public LoginData getData() {
    return data;
}

public void setData(LoginData data) {
    this.data = data;
}

public Boolean getError() {
    return error;
}

public void setError(Boolean error) {
    this.error = error;
}

public String getMessage() {
    return message;
}

public void setMessage(String message) {
    this.message = message;
}

}

login data

public class LoginData {
@SerializedName("id")
private String id;


@SerializedName("name")
private String name;

@SerializedName("phone")
private String phone;

@SerializedName("otp")
private String otp;


@SerializedName("created_at")
private String created_at;


@SerializedName("updated_at")
private String updated_at;



@SerializedName("email")
private String email;



@SerializedName("email_verified_at")
private String email_verified_at;


public String getId() {
    return id;
}

public void setId(String id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getPhone() {
    return phone;
}

public void setPhone(String phone) {
    this.phone = phone;
}

public String getOtp() {
    return otp;
}

public void setOtp(String otp) {
    this.otp = otp;
}

public String getCreated_at() {
    return created_at;
}

public void setCreated_at(String created_at) {
    this.created_at = created_at;
}

public String getUpdated_at() {
    return updated_at;
}

public void setUpdated_at(String updated_at) {
    this.updated_at = updated_at;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public String getEmail_verified_at() {
    return email_verified_at;
}

public void setEmail_verified_at(String email_verified_at) {
    this.email_verified_at = email_verified_at;
}

}

here is the api response from the postman

{
"error": false,
"data": {
    "id": 4,
    "name": "isra ahemd",
    "phone": "999005491",
    "otp": 1188,
    "created_at": "2020-05-22T17:31:32.000000Z",
    "updated_at": "2020-05-28T08:04:47.000000Z",
    "email": null,
    "email_verified_at": null
},
"message": "please verify your number with this code 1188"

}

and here is the method in loginActivity which make the crash exactly here (if (response.body() != null ? response.body().getError() : true){)

 private void register(final String name,final String phone) {
    loading = ProgressDialog.show(LoginActivity.this, getString(R.string.loading), getString(R.string.wait), false, false);
    loading.setCancelable(false);
    loading.setCanceledOnTouchOutside(false);
    NetWorkApis netWorkApis = ApiClient.getClient(ApiClient.BASE_URL).create(NetWorkApis.class);
    Call<LoginResponse> settingResponseCall = netWorkApis.register(name,phone);
    settingResponseCall.enqueue(new Callback<LoginResponse>() {
        @SuppressLint("LongLogTag")
        @Override
        public void onResponse(@NotNull Call<LoginResponse> call, @NotNull Response<LoginResponse> response) {
            if (response.isSuccessful()) {
                Log.i(TAG,"respnse : "+ response.toString());
                Log.i(TAG,"respnse body : "+ response.body());
                Log.i(TAG,"respnse message : "+ response.message());
                Log.i(TAG,"respnse message : "+ response.errorBody());
                if (response.body() != null ? response.body().getError() : true){
                    Utility.showAlertDialog(getString(R.string.error), response.body().getMessage(), LoginActivity.this);
                    loading.dismiss();

                }else {
                    LocalSession localSession = new LocalSession(getApplicationContext());
                    localSession.createSession(Boolean.TRUE,response.body().getData().getName(),response.body().getData().getPhone(),
                            Integer.valueOf(response.body().getData().getId()),response.body().getData().getOtp());
                    loading.dismiss();
                    startActivity(new Intent(getApplicationContext(),OTPActivity.class));
                    finish();
                }

            }else {
                Log.i(TAG, response.errorBody() != null ? response.errorBody().toString() : "response is null");
                Utility.showAlertDialog(getString(R.string.error), getString(R.string.servererror), LoginActivity.this);
                loading.dismiss();

            }
        }

        @SuppressLint("LongLogTag")
        @Override
        public void onFailure(@NotNull Call<LoginResponse> call, @NotNull Throwable t) {
            Log.i(TAG, t.getLocalizedMessage());
            loading.dismiss();
            Utility.showAlertDialog(getString(R.string.error), getString(R.string.servererror), LoginActivity.this);
        }
    });
}

**please note that the app is worked fine in the debug apk this problem is just in the release **