I made a minecart with golem road on the rails around my house. If i go out from my house and exit minecraft, the golem on the minecart will lost if i comeback to my house

What I expected to happen was....:
When I comeback to my house, the golem on the minecart should be road on the rails

What actually happened was....:
When I comeback to my house, i'm not seeing the golem on the minecart again

Steps to Reproduce:
1. In survival, add rails and some powered rails around your house
2. Make a minecart, throw it to rails and move it
3. Make the iron golem on rails. The minecart will move to the golem and the golem will on the minecart
4.Go out from your house until you can't see all of your house
5. Exit minecraft pe
6. Play minecraft pe
7. Go back to your house
8. Now, find the golem

I'm use Samsung Galaxy Prime (SM-G530H)