My Fiance is extremely sensitive to oral sex

Hey all. My fiancé and I are having our first child together and I am currently on pelvic rest. But I am DYING to just have some intimate time with him. I enjoy giving him head and would like to just do that and I will be satisfied 😌 but he is extremely sensitive on his dick when it comes to oral. I give him head almost every time we have sex but he can never finish due to how ticklish he gets. He said he's only ever came twice in his life from head and I'm wondering if you guys have any tips? I've found the closest We've gotten to him finishing is when I was giving him head while he was laying down and I was on the side of him. Any advice is welcome 🙏