Turtles not laying eggs after breeding

After multiple attempts to breed turtles, I am still left with 0 eggs being laid. I've flown 1000's of blocks away to generate new parts of the world and thus spawn new turtles, and yet they only perform the breeding action. Neither go to their spawn beach to lay eggs, they only swim around in the water aimlessly. I've tried making creative worlds to test this out, both with Spawner eggs and naturally spawned turtles. Not sure why this is happening, I only want the turtle shell helmet!