Soft login is a feature of spring security. When a user logs into an application and chooses to remember his credentials by clicking ‘Remember Me’ button, his credentials are stored in a cookie. After session expires on browser, he is logged in again taking credentials from cookie.
A soft logged in user can browse the application, but pages like account page and checkout pages are secured by hard login. To access these pages, he has to provide password again.
If you want to switch the feature off, then go to spring security file of your project and comment the below line.
This will disable the feature for your storefront.