Samsung Galaxy Note 8 (US-version) — used.samsung messages notification

Please help me understand how used.samsung messages works in your google activity. My boyfriend gets multiple of these notices throughout the day but they do not show up on his text message history. I think he's using a separate samsung messenger app. When he gets a message notice it shows up on the phone dial pad where the numbers are and a camera. The camera switches quickly and flashes a messages icon when I believe he gets a notice. He tells me thats standard for Samsung however over the last 4 years it never happened before.