The animals in my world are enclosed in fences and when I go mining and come back up they're all gone even tho the fence gate is closed and there is no way they can escape, my horse who I also gave a name via name tag also disappeared even though its on a leash tied to a fence post...

Thr fences have no block near it nor carpets on top of it, just literally a whole fenced out area for my animals and a single fence door (which I always leave closed) for my entrance...

In the screenshots I sent, the first two pictures is where my horse is suppose to be found but all thats there is just its leash, the 3rd picture is the picture of my small chicken farm that has all the chickens suddenly disappear (and without a trace)....