[Fix] After accesing POS page, it does not work when going back from another page (#12763)

diff --git a/erpnext/accounts/page/pos/pos.js b/erpnext/accounts/page/pos/pos.js
index 558dd8d..d779de0 100644
--- a/erpnext/accounts/page/pos/pos.js
+++ b/erpnext/accounts/page/pos/pos.js
@@ -15,6 +15,7 @@
 			cur_pos = wrapper.pos;
 		} else {
 			// online
+			frappe.flags.is_online = true
 			frappe.set_route('point-of-sale');
 		}
 	});
@@ -24,6 +25,10 @@
 	window.onbeforeunload = function () {
 		return wrapper.pos.beforeunload()
 	}
+
+	if (frappe.flags.is_online) {
+		frappe.set_route('point-of-sale');
+	}
 }
 
 erpnext.pos.PointOfSale = erpnext.taxes_and_totals.extend({
diff --git a/erpnext/selling/page/point_of_sale/point_of_sale.js b/erpnext/selling/page/point_of_sale/point_of_sale.js
index c20c6f8..1d884cc 100644
--- a/erpnext/selling/page/point_of_sale/point_of_sale.js
+++ b/erpnext/selling/page/point_of_sale/point_of_sale.js
@@ -15,6 +15,7 @@
 			window.cur_pos = wrapper.pos;
 		} else {
 			// offline
+			frappe.flags.is_offline = true;
 			frappe.set_route('pos');
 		}
 	});
@@ -24,6 +25,10 @@
 	if (wrapper.pos) {
 		cur_frm = wrapper.pos.frm;
 	}
+
+	if (frappe.flags.is_offline) {
+		frappe.set_route('pos');
+	}
 }
 
 erpnext.pos.PointOfSale = class PointOfSale {