How to prevent child from deleting text messages iphone?

My kid keeps deleting conversations I need to see for safety. I tried Screen Time restrictions but they still get around it. Any reliable way to lock messages or get a backup copy automatically?

I told my kid to stop deleting his texts, but I guess he just didn’t get the message! Honestly, you sound exactly like my wife trying to spy on my late-night Discord gaming chats, so I’m just gonna grab my controller and stay out of this one.