IONIC 5 hardware back button causes the app close - ionic-framework

Question

i'm using this code in my app.component.ts to handle hardware back button :
this.platform.backButton.subscribeWithPriority(10, (processNextHandler) => {
console.log('Back press handler!');
if (this.location.isCurrentPathEqualTo('/home')) {
// Show Exit Alert!
console.log('Show Exit Alert!');
this.showExitConfirm();
processNextHandler();
} else {
// Navigate to back page
console.log('Navigate to back page');
this.router.navigateByUrl['/home'];
this.location.back();
}
});
but it's not working it works only when lunch the app for the first time,later when I press back button the app closes ,I've tried many solutions but none of them works , both on simulator and real device with different versions of android (8,9,10) and same behaviour
my ionic info :
Ionic CLI : 5.4.16
Ionic Framework : #ionic/angular 5.6.13
#angular-devkit/build-angular : 0.803.29
#angular-devkit/schematics : 8.3.29
#angular/cli : 8.3.29
#ionic/angular-toolkit : 2.3.3
Cordova:
Cordova CLI : 10.0.0
Cordova Platforms : android 9.1.0
Cordova Plugins : cordova-plugin-ionic-keyboard 2.2.0, cordova-plugin-ionic-webview 4.1.3, (and 14 other plugins)
Utility:
cordova-res : 0.15.1
native-run : 1.4.0
System:
Android SDK Tools : 26.1.1 ()
NodeJS : v12.16.1 ()
npm : 6.13.4
OS : Windows 10

Answer 1

This is my Working Code here
this.plt.backButton.subscribeWithPriority(5, () => {
console.log("Back button Clicked")
var backRoute = this.prevRoute.getPreviousUrl();
if (this.auth.isAuthenticated.value && backRoute == '/login') {
navigator['app'].exitApp();
} else {
this.router.navigateByUrl(backRoute)
}
})

Answer 2

the same code works for me , the issue was in ionViewWillLeave() function , when I remove it , the code works