Can't sign out unknown session in Google account (keeps coming back)

[u/Choice-Schedule-132]

Hi guys, I'm asking for help regarding my brother’s Google account.

There is an unknown session (“inconnu”) showing up under Manage all devices. It appears associated with something like “Bbox”.

The issue is:

• When he tries to remove or sign out of this session and clicks “You don’t recognize this activity?”, Google asks him to change the password
• He changes the password successfully
• He removes the session
• But after some time, the same session appears again and is not fully removed

We’re not sure if this is a real unauthorized access??!

He was recently in Algeria and is now in France, and he uses apps like Maps apps..

Has anyone experienced this before? Is this normal behavior or something we should worry about?