On my server, the players are reportedly getting invalid player data whenever they choose Elytrian. To reproduce this, choose the Elytrian origin, play for a bit, and then you will randomly get kicked. After getting kicked, you no longer can log in due to invalid player data.

Here are all the mods that are on the server: https://drive.google.com/drive/folders/125jXAJAS0OFnSGPNEhTWZxO3EIcCe_NB?usp=sharing

I am currently using fabric mod loader version 11.7 and Minecraft version 1.17.1.