Any way to fix this?

Chunks don't seem to be loading at all and leave huge gaps and when flying to them it crashes my game. This was the last message in my log before it crashed: [15:15:12] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 2468ms or 49 ticks behind I can share my whole log if necessary, theres a lot of /WARN] messages like that if thats relevant also using 2.0 nightly and the test iris build