I’m going to say this as advice, please get him a new car seat. Those seats only go up to like 40 inches I believe and it looks like he is too tall for it. My daughter was using the same one and I didn’t realize the height limit and she was 42” before I realized she shouldn’t be using it anymore. Get him a harness booster, they’re really cool they have a harness and then when he outgrows that then it converts to a booster. Graco has one for under $100.