Wattpad app (17+) appears on screen time but was not downloaded

My child is age 11. Screen time shows that she is spending a lot of time on the Wattpad app (17+), always a few minutes less than the time spent on Safari. However, I have not approved her to download the app, and it does not appear on the list of apps on her iPad or iPhone. There is no app to delete. I’m concerned the app has inappropriate material. But I am also concerned that it’s tracking all her safari activity. I even added wattpad.com to the list of websites not allowed, but it keeps appearing on screen time. Has anyone experienced this and/or know how to get rid of wattpad?