When loading my realm I receive the message "Unable to connect to world"

I recently created a new world on my realm. Now a few days later it gives me the message "Unable to connect to world" whenever I try to load it up. This problem is also occurring to my friends on the realm. I have tried using backups but they also fail to load, it won't even let me download the world to play it off the realm. Closing and reopening the realm isn't an option either for every time I try to a message pops up saying "Failed to close realm".