Can not redirect to specific page when click on the notification in background

Ionic Framework ionic-v3
1

Hello,
We are working on an app project with ionic3 for android and having an issue with notification :
We can not redirect to specific page in our page when click on the notification in background

This is the code :

pushObject.on('notification').subscribe((notification: any) => {
      console.log('Received a notification', notification);
      //Notification Display Section
 if (notification.additionalData.foreground) {
  let confirmAlert = this.alertCtrl.create({
    title: this.idealParam.nomLab,
     message: "Vous avez un nouveau message",
     buttons: [{
          text: 'Ignorer',
          role: 'cancel'
        },
 {
          text: 'Voir',
          handler: () => {
          this.nav.push(DetailsPage, {analyse:notification['additionalData']['moredata']});
          }
        }]
      });
      confirmAlert.present();
      //
    }
  if(notification.additionalData.coldstart == false){
  this.nav.push(DetailsPage, {analyse:notification['additionalData']['moredata']});
    }
    });

Thank you for your precious help
Best regrads