disconnection from realm

I have created a realm so that my girlfriend and I can play a game with each other without having to be next to each other or on at the same time. The realm that I have created is just the two of us in the realm. We have done a lot with the realm and then it started disconnecting both of us from the server at the same time, and then it wouldn't save any of our work. At first I thought that it was just a fluke but then it continued to happen. We thought that it was something that was wrong with the realm so we created a new realm and linked it with a new world. At first it seemed to be fine, but then after a day it started up again. What could cause this? We just wanted to have a game to play together, and it doesn't work for us at all now and its money that is being wasted. Please help?