We've been having many issues with our Realm for months. It hasn't been saving consistently, and will kick all players from the server at the same time every few hours, rolling back 15-30 minutes each time. I tried downloading the last world backup two days ago, but after a few hours, I was still on the "preparing download" loading screen, and since then none of the players have been able to access the realm at all. 

Thanks for you help!