Simply starting game messes up my whole internet connection

Simply starting Minecraft (on Xbox One "Windows 10 Edition") messes up my xbox's connection to the internet. If Im in a party while starting MC, it will disconnect me and not allow me to connect to parties. Joining my realm (which I pay for) messes up my xbox's connection. Everytime I join the realm it is EXTREMELY laggy to the point where I cant play. Every single other game on my list is fine and this does not happen with. Only with MC. As I said, I pay for the realm which has 7 other people playing on it, yet I cant even play on it myself....