I'm changing version of third party server to play w/ my friends

What I expected to happen was...:
Entity(Minecart with hopper and item frame exists)

What actually happened was...:
Two entity loss

Steps to Reproduce:
1. Create server at 1.17.1 ( I'm using aternos)
2. place minecart with hopper and item frame with something inside
3. change to 1.16.5

Hop in and see those are loss