SPO: Change of Quick link navigation for Team site

Hi @Sharepoint community,

I am not able to restore to default navigation template produced when a new team site is created.

I was trying different site templates on my team site and choose a TEAM collaboration template.

Unfortunately, this changed my quick link navigation which is cumbersome to make edits. 

 While clicking on edit ,it opens a new window (fig.1) directed towards 'Navigation settings' - and gives only 1 level of sub linking. 

Fig 1:

However, previously , before changing the template style , the navigation has these components:

fig 2: 

How can I activate this type of navigation again? it just makes things so easier. 

Thank you in advance.