Everything was working fine until we got the message "incomplete set of tags..." at around 2 hours into our last world so we made the decision to restart the world from scratch. One of our friends was able to stay on the server until he chose to disconnect and when he tried reconnecting, was met with the same message. We deleted world data and player data before generating a new world.
After restarting, we would continue to receive the message every time we'd try to connect on a fresh world. We double-checked our client mods and server mods and everything matched. The only outlier would be the client-side mod fpsreducer. We are playing on version 1.16.5 using Forge 36.1.0.
These are the logs from the latest attempt https://mclo.gs/bkHoKLT