Sharing session with no CI app

Hi guys!
I´m having a hard time trying to share the same session between a native php app and a ci app the situation is the next:
We are currently trying to migrate an entire app to CI4
the native php app produce a session and at some time make a post to CI app when i land to the CI app (works great) the session does not pass to CI
im playing with the session files cause i think it search for the same ci_session name i already change the both sessions names to try to mach eachother (with no luck)
the session file that the old app is creating, got the name: sess_d5agcbecpo9jhq8951g59g67na
meanwhile when the app lands at ci this produce this file: mhp_session2ag2pf95sto44ukte3huptrt1gnap3k5  (mhp_session is my cookie_name in .env file)
Session are created anew.

Tip: when i click back in explorer it produce another session file with this name: sess_d5agcbecpo9jhq8951g59g67na (with no data and crash the sistem)

Another Tip in ci app im using session service from CI4 in my BaseController

Code:

$this->session = \Config\Services::session();

Thanks in advance!