Internal Server Error in Minecraft Realm

I have a Minecraft Realm that expired a while back. Though, only about a few days ago, I purchased a subscription of 30 days for it. It's set to peaceful.. It's also set to creative as well.. But when I try to open up the Realm, an "Internal Server Error" appears on the screen. This happens to my friends who try to get on the Realm as well. I'm not sure if it's because of the version that the Realm was created on or something else. If someone could help fix this problem, I would very much appreciate it.