SP initiated okta login failing if there is no active admin session

Hi Team,
I am trying to login to OKTA from my application login page, via auth API(create session with credentials) in the backend. But I noticed that if there is active admin session(OKTA), then the user is able to login to the application. Else, it is redirecting to the OKTA login page.
I don’t want my user to confuse with another login(OKTA) page.
How can I achieve this?