Realm crash

A couple of mates are playing on my realm and all having our games crash and sometimes not start up 

What I expected to happen was...: 
go into the game as usual and be able to play **

What actually happened was...:
When we can load up the game it last no more than 15 minutes then we can't open chests can't take damage etc

Steps to Reproduce:
1. Happens randomly when we start up the game
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