Help!!! Equestrian Center Menu is Not Working!!!

But was your sim on the lot, or just outside it? Because it might be a glitch (in which case you could probably try to replace the Center), but it might also just be that when you're on the lot, you don't get the menu.

So, if you're not sure, where your sim was exactly, perhaps you should try clicking the building with your sim definitely outside the lot, the next time it's 5 PM.