Turtles unable to breed

So I try breeding turtles using seagrass, right? And then, once you feed them they produce hearts and just sit there. Even when they moved I followed them but they didn't do anything, because where I bred them was their home beach. Happens in both creative and survival. And now, a few days ago, I tried feeding them they won't even eat for some reason. I hope you have a solution. I really need the Turtle Shells.