missing data after redirect

I have an old CI 2 project back to '11. My task was to change http to https. The frontend works well, but at backend I have problems. Step by step process:
- at the login controller the user successfully logs in (I use DX_Auth auth library) it puts all data (username, user_id, logged_in etc) to session. I debugged, all data are there.
- after positive login there's a redirect to admin/index page. like redirect('admin/index');
- here in the constructor is a login check, but the check fails because nothing in the session previously put into it.
it seems that somehow at redirect these data are losing..  

Two facts:
1. it was working before changing to https
2. this project is set up on my computer using MAMP, the login and redirect into admin works also well.

I see in CI 3 docs, that redirect() has a second parameter, like 'https'. Maybe that's the solution, or?

Any idea?
Thanks