title: Subscribe to a subject only fired once
body: <p>I created a service in order to get datas from an API and use a Subject to get theses datas from my component (LoadTenants is called at the app initialization): </p>
  
  <p>The service :</p>
  
  <pre><code>@Injectable()
   export class TenantService{
    public tenants;
    private tenantSubject = new Subject&lt;any&gt;();
  
  constructor(private http: HttpClient) {
  }
  
  LoadTenants() {
      this.http.get(TENANT_URL).subscribe((data: any) =&gt; {
          this.tenants = data;
          this.setTenants();
      });
  }
  
  setTenants() {
      this.tenantSubject.next(this.tenants);
  }
  
  getTenants(): Observable&lt;any&gt; {
      return this.tenantSubject.asObservable();
  }
  
  getSyncTenants() {
      return this.tenants;
  }
  }
  </code></pre>
  
  <p>The component : </p>
  
  <pre><code>public tenant;
  subsciption: Subscription;
  
  constructor(private tenantService: TenantService) { }
  
  ngOnInit() {
          this.subsciption = this.tenantService.getTenants().subscribe((datas) =&gt; {
              this.tenant = datas;
          },
              error =&gt; console.log('Error : ', error)
          );
      }
  }
  
  ngOnDestroy() {
      this.subsciption.unsubscribe();
  }
  </code></pre>
  
  <p>Everything is working fine on the first load, but if I navigate to an other component and come back to this one, the subscription is not fired resulting on void datas in my template.</p>