added locale backup + en support

src/app/pages/unavailable/unavailable.component.ts

@@ -1,4 +1,5 @@
-import { Component, OnInit } from '@angular/core';
+import {Component, OnInit} from '@angular/core';
+import { Location } from '@angular/common'
 
 @Component({
   selector: 'app-unavailable',
@@ -7,9 +8,14 @@ import { Component, OnInit } from '@angular/core';
 })
 export class UnavailableComponent implements OnInit {
 
-  constructor() { }
+  constructor(
+    private location: Location) {}
 
   ngOnInit(): void {
   }
 
+  retry() {
+    this.location.back();
+  }
+
 }