Describe the bug
when exchange items on computer,bungeecord will throw an error and the player will be sent to the fallback server.

Crash report
https://paste.ubuntu.com/p/RgcNM7kHdw/

To Reproduce
If applicable, the steps to reproduce the behavior:

1. run the server with bungeecord (I am using waterfall proxy)
2. exchange items on the computer block
3. see the error on console

Screenshots
If applicable, add screenshots to help explain your problem.
GIF:
https://upload.cc/i1/2019/10/05/peATOR.gif

Please complete the following information:

• Minecraft Version: 1.12.2
• Mod Version: 6.3.1