iPhone 13 recent update to 18 has my phone listening and typing conversations.

This never happened before updating to 18 and I can't find any setting to turn off whatever is causing this. Siri is off, and I can't find AI when I search for it in settings. I am trying to help a family member that has this phone. They'd really like this to stop; it's unnerving and invasive. I'd appreciate any help. I searched for help via the community here for questions that tie to the update/problem, but wasn't successful.