Client disconnects from server when attempting to use any machine

[Processhf]

23.12 21:36:42 [Server] Netty Epoll Server IO #14/ERROR java.lang.NullPointerException
23.12 21:36:42 [Disconnect] User Fascina has disconnected, reason: Internal Exception: io.netty.handler.codec.EncoderException: java.lang.NullPointerException

This error is thrown every time a machine is attempted to be used on our server. We are running FTB Cotton v1.1.0 modpack.

We had no issues with the mod previously until an issue where we couldn't load any chunks with an Astromine machine in it. Upon restarting the server, we noticed all Astromine machine-containing chunks were deleted and regenerated, along with the machines causing a disconnect upon using them. This issue does not happen in Single player.