Connection

My husband created a realm a couple months ago for the family. Yesterday no one could connect on any device. We are on Xbox Series X. We also tried mobile, PC and Xbox One. We can join everyone else's realms. Just not his. It's not our internet either. My husband works for Comcast. We have uninstalled reinstalled. Cleared cache. Reset Xboxs, then we copied the realm to replace it and it said it can not replace realm. We even checked our payment status and it's paid.