Unable to Connect

My son and I have several worlds on two ipads that we play in together. Now we are suddenly unable to join each others worlds. No changes were made other than ipad updates and app updates. Still, I have double checked all the settings on our microsoft accounts and the settings of the actual worlds as well. We started another survival world thinking we would just have to give up playing in the others. Initially we were able to both join but it went back to saying unable to connect the next time we tried to open it.