Tracking web activity via Google on S3

A

AC Question

My son has a Samsung S3. He uses the stock android browser. Previously, I could see all of his searches on this browser when I logged into his Google account. However, now the history is no longer showing his searches. All I see when I look remotely at "web & app activity" are the apps he is using each day. I have checked within his Google settings and everything within those options is enabled.

If I am logged into his Google account from MY phone or MY computer, and I search something while still logged in, it immediately shows in his Google web & app activity history. But HIS searches from HIS phone are not showing up, and I know he's using this browser (when I look directly at the phone there are browser windows open).

Could someone please tell me what the issue could be that is preventing Google history from showing his searches on the android browser?

Thanks!