Redirect to another page if the user is logged in when pressing again the login button on menu bar

Firest of all you have to make sure that is_page() is right. I think the right syntax is

is_page( 'min-konto' )

or

is_page($pageid)

then the function should be

if( is_page( $account_settings_page_id ) && is_user_logged_in() ) {
   wp_redirect( home_url( '/dashboard/' ) ); 
exit(); 
}