I [20F] put restrictions into my boyfriend’s [20M] phone without telling him

I [20F] and my boyfriend [20M] agreed that we didn’t want porn in our relationship. want to know what people think about this because I don’t feel like I’m really in the wrong since he’s been lying to me for years. Me and my boyfriend have been together for 4 years. About 3 months into our relationship, I told him I’m not okay with him watching porn/masturbating to other women. He agreed he wouldn’t. He told me he would be upset if I did it too.

Two years down the line, I was looking something up on his phone, and there it was in his recent searches. I broke down badly, for days, and he comforted me and told me he wouldn’t do it again. Ever since then, this situation has happened probably 4-5 more times, each time I tell him I’m going to leave and he begs me to stay, cries, and I fall for it.

He would stop for some time, a couple months, then I’d find it again. At this point it felt like not only did he do what makes me uncomfortable, but he’s lying to me over and over about something he knows and has seen hurts me deeply. It has been a long time since I’ve found it and he has given me the login to his instagram since I’ve found stuff on there multiple times. He also sold his iPad (HIS CHOOSING) to make me feel better.

Well a couple months ago I turned screen time on on his phone and locked it with a passcode so he can’t turn it off. I checked it periodically when I first turned it on, and there was nothing, so I left it for a few months. Yesterday I checked it when he was sleeping and over the past month (and probably longer) he had been on pornhub and other websites like it at least once a week. At this point I don’t feel so hurt about it cause I’ve read some other posts on here and people say that almost all men watch it and there’s really nothing you can do. But I still would rather him not watch it, and he’s still lying. So I went into the screentime settings and turned on restrictions for adult websites. His phone is the only device he has. I know that he will probably not bring it up to me because he knows he’s wrong for looking at it based on everything that’s happened in our relationship.
This is the only big issue we have had with trust in our relationship and apart from this he is my best friend and I love him so much and he does me. Should I tell him I found it again? Is it even worth it to have that discussion again or am I within my rights in just blocking it on his phone? We had talks previously about him downloading porn blockers and he agreed but they costed money, but I just realized I could do this and I did. Idk

TLDR; I told my boyfriend from the start to not watch porn and he agreed. I’ve found it several times and now I’ve put restrictions on his phone so that he can’t use adult websites and the setting is locked by a passcode only I know. He doesn’t know I did this but if he finds out he’s probably not going to say anything. Should I try talking to him again or just leave it?