App doesnt open div when there is not internet connection

Ionic Framework ionic-v3
1

Hi!

I have an app using ionic 2 and Im trying to open a div when the user clicks on a button.
I have a list of cards that each one has an id. I’m using DOM to manipulate the view but this just works when I got internet connection, if a turned off the div that I clicked dont show up.

my code:

itemTapped(event, bloco) {
   if(this.reading.block_unit === this.READING_BY_DIVISION) {
     var id = bloco.id_division;
     var classname= document.getElementById(id).className;
     this.id_division = id;
     if(classname == "hide") {
         this.openDiv(id);
       if(this.last != undefined && this.last != id) {
           this.closeDiv(this.last);
       }
     } else {
       this.closeDiv(id);
     }
     this.last = id;
   } else {
     this.nav.push(UnidadePage, {
       portal: this.portal,
       status_portal : this.status_portal,
       division_id: bloco.id_division,
       unidades: bloco.units,
       division_name: bloco.name,
       reading: this.reading
     });
   }

openDiv(id) {
      this.value = "";
      this.note = "";
      this.base64Image = "";
      if(this.network.isNetworkAvailable()){
        this.readingService.getByDivision(id,this.reading.type).subscribe(
            data => {
                if (data.length > 0)
                  this.value = data[0].value;
            },
            err => {
                console.log(err);
            }
        );
      }
      document.getElementById(id).className = "";
      document.getElementById("camera-" + id).className = "";
      document.getElementById("note-" + id).className = "";
  }