Please use this thread going forward: [HR] Horse/Foals refuse to play with Ball | EA Forums - 12291052
Hey there @Salitice luckily there is a workaround, keep replacing the ball with a new one from build mode and the horse should play with the new ball. You'll have to do this often and it works for me.
There's an open bug report for the problem attached here if you'd like to go to the first post on page 1 and click the Me Too button and add a Reply you should be prompted with a bug template to fill in with the platform you are on and what content you have installed. Lots of players have this issue.
Hope this helps!
I'm having this issue too. I think balls last for about 10 days or so? I've played about 3 in game weeks and replaced the balls twice now.
I'll see if I can test the thing with the enclosed area, since I have two horses and two balls.
