I don't know anything about ARs

Hey all, I built an AR in 2020 after the dude who now lives in the white house won, just in case his hair brained schemes worked and they did manage to get rid of them. I was more-so banking on the dude who sleeps with models and owns a cool house in Florida winning, and spending that money instead on a Ruger Mini-14 which is much more my speed. But hey, ya know? It didn't work out that way.
So, I put all the pieces together with my ex-wife's now second ex-husband (we became friends to spite her, and we were raising kids together), he is a mechanical engineer who works for a local gun company so don't @ me on his building skills, I trust him. It worked fine until this weekend, when all of a sudden my trigger won't reset? It chambers another round, but I have to flick the safety on and off to get the trigger to reset. Is there anyone out there that can help me with this issue or know what it might be? I'd be appreciative of any help! I really don't know s from shinola.
Second ex-husband and I haven't seen each other since their divorce was final cuz he actually liked my kids and was nice to them, and had a hard time not having them in his life anymore so I give him space.
My life is indeed a soap opera in case you ever want some tea.
Thanks.