Shulker box dissapeared

I was in the end making an enderman farm and I was on my way to the area where i spawn into when i go to the end where my shulker boxes were. and they were just gone. I had 2 of them, one with all of my tools and armour, and the other with all my materials to make the farm. When I get there, they are just gone. I lost all of my items.