Both my friend and I updated to 1.16.0.55 Beta and upon my friend joining all his previous items before we updated disappeared (My items unaffected), and he spawned at the default worldspawn, after rejoining and acquiring new items, my friend crashed and the above error happened again. We are connected to the same WiFi and my friend joins my worlds from his android 10, while I play windows 10. I hope it get fixed, and gooduck Minecraft team!