Items and mobs missing

Hello, I'm reporting that the day before I played Mine, Make a Farm, and I got excited about the game again. Yesterday my phone shut down due to low battery. I'm not sure if I saved the world the conventional way. However, today I opened the world and discovered that my items were gone, and I was in the respawn state. So far so good, some creeper must have killed me, everything is fine. However, when I opened my end chest, I saw that there were no items there, which is terrifying because I had several valuable things. I also noticed that my dog and cat were missing. This is completely frustrating and terrifying. Out of nowhere, the game eliminated these entities. I checked, and it didn't affect item frames, but affect mobs and armor stand.