How to navigate from tab2 to tab1 on clicking device back button in ionic3

I am following this

After login i am using this key to navigate to next page this.navCtrl.setRoot(“tabs”); i am automatically seen home tabs / tab1 as selected in my tabs.

I have totally 5 tabs Tab1,Tab2,Tab3,Tab4,Tab5.

Initial Tab1 is getting selected. When i navigate to any tab like Tab2/Tab3 and click on device back button i am not able to navigate to my previous Tab.

My Understanding:

Since i have 5 Tabs so when every tab is selected new stack is been initiated.

I believe i have to navigate to Stack to Stack is it possible and if so any piece of advice will help me .