Issue description:
able to fly on the server
Steps to reproduce:
Players can fly if they exit the server game when taking the elevator and re-enter the server.

Versions:

• Minecraft: 1.12.2
• Forge: 14.23.5.2855
• CompatLayer (only if on Minecraft 1.10 or 1.11):
• McJtyLib:3.5.4
• RFTools:7.73