Geolocation doesn't work on mobile - ionic v4

Hey guys, i’ve got a problem using geolocation plugin:
this is my code on home.ts

import { Component, OnInit } from '@angular/core';
import { NavController, LoadingController } from '@ionic/angular';
import { Geolocation, GeolocationOptions ,Geoposition ,PositionError  } from '@ionic-native/geolocation/ngx';
import { NativeGeocoder, NativeGeocoderResult, NativeGeocoderOptions } from '@ionic-native/native-geocoder/ngx';

  selector: 'app-home',
  templateUrl: '',
  styleUrls: [''],
export class HomePage {

  constructor(private loadingController: LoadingController, private nav: NavController, private geolocation: Geolocation, private nativeGeocoder: NativeGeocoder) { }


  x = 0
  y = 0
  code_postal = 0

  ngOnInit() {
    this.geolocation.getCurrentPosition().then((resp) => {
      this.x = resp.coords.longitude
      this.y = resp.coords.latitude
       alert("x: "+this.x)
       alert("y: "+this.y)

      this.nativeGeocoder.reverseGeocode(45.8333, 5.6, { useLocale: true, maxResults: 1 }).then(
        (result: NativeGeocoderResult[]) => {
          this.result = result
          // alert(data[0].postalCode)

          // var data = result
          // alert(data[0].postalCode)
      ).catch((error: any) => alert("erreur: "+error));

    }).catch((error) => {
      alert('Error getting location'+error);


I’m using geolocation plugin to get position and native geocoder plugin to get the postal code of the place! The geolocation work on ionic serve but the native geocoder need to start on emulator or mobile; so i build it and it work properly. Then, i add http plugin to get some data from a website via the position i got; at the moment when i used the plugin, i got any result on emulator or mobile, even the geolocation doesn’t work! Before i start this project, i make one projetct that only use geolocation who work properly on mobile; but this project doesn’t work with the other! I tried a new project using geolocation, it doesn’t work too! :confused: so i need help if someone know what’s wrong!
If only the project with the http plugin does’nt work, its only code problem or plugin, but 3 projects doesn’t work, its another problem.
Thanks in advance