Trying to join my realm and it says "Unable to join world"

This has happened a few times, most of the time it will last an hour then I can join again, now its starting to happen more frequently and longer. I will try to join my realm and the message "Unable to join world". I have tried everything, exporting a new realm, closing the realm and opening it again, shutting down my pc and turning it back on. It just wont work and Im really tired of it. If any more specific information is needed let me know.