Realm Disconnection

My realm will just randomly crash. Me and my friends will be playing on my realm (keep in mind I am the realm owner) and even though I am actually PLAYING on the realm, not configuring it, it will say "server closed" and kick EVERYONE off the realm, though the realm will not actually close, it will just kick everyone off and backtrack a few minutes of progress. No matter what I try, it just will not stop. Any suggestions greatly appreciated.