Boyfriend in dating group?

I was scrolling Facebook the other day and became aware of my boyfriend being in a “__ (location) dating socials” group.. we’re in a bit of a rough patch at the moment so I confronted him about it. He claims he doesn’t know how he ended up in there, and when he checked it said he’d been a member since June 2017 (we were still together though at this stage so to me that doesn’t help his case).

What would you do?

I would have thought me confronting him would’ve made him delete it and all sorts. But he’s made no attempt to delete himself from the group either. His profile blatantly states he’s in a relationship and his profile pic is of us, so all I keep thinking is it’s a stupid way to attempt to cheat if you’re advertising you’re in a relationship.