Google Maps Not loading on re entering page

Ionic Framework ionic-v3
1

I am having a problem with google maps, when i enter the page on first load it pushes the markers to the map, if i leave the map and then re-enter the page it doesn’t load the map markers…

here is my add map code below:

constructor(public navCtrl: NavController,
    public maps: GoogleMapsProvider,
    public platform: Platform,
    public locations: LocationsProvider,
    public popoverCtrl: PopoverController,
    public apiProvider: ApiProvider) {

      this.apiProvider.getShops().subscribe(shops => {
          this.shops = shops;
        });
  }

  ionViewWillEnter() {

    this.platform.ready().then(() => {

      this.apiProvider.getShops().subscribe(shops => {
          this.shops = shops;
        

      let mapLoaded = this.maps.init(this.mapElement.nativeElement, this.pleaseConnect.nativeElement);
      let locationsLoaded = this.locations.load();

      Promise.all([
        mapLoaded,
        locationsLoaded
      ]).then((result) => {

        //let locations = result[1];

        for (let shop of this.shops) {
          this.maps.addMarker(parseFloat(shop.Latitude), parseFloat(shop.Longitude), shop.Name, shop.Website, shop.Logo, 
            shop.OpenMon, shop.OpenTue, shop.OpenWed, shop.OpenThu, shop.OpenFri, shop.OpenSat, shop.OpenSun,
            shop.AddressLine1, shop.Postcode, shop.City, '1', '1');
        }

      });
    
    });
    
  });

  }