Codeigniter 3 cannor remember session

UPDATE:
Now I found that CodeIgniter is generating session id 3 times once a page load. I don't know what the cause is, but it does remember session. The remembered session just got replaced by those 2 new generated ids.

But I still wondering, why does it generate 3 times when opened in pc, but generate only 1 time when opened in mobile.

I tested it in pc with Google Chrome, IE11, Mozilla Firefox, and Vivaldi, but none of them works as expected. So browser compatibility is not the problem.


ANOTHER UPDATE:
When it accessed with mobile, it will include __ci_last_regenerate in the session file. But if it accessed by pc, it WILL NOT include the __ci_last_regenerate in the session file. I think, this is the cause why the session regenerated multiple times. But still have no idea what causes the __ci_last_regenerate didn't stored in the session file.