hey correct me if im wrong, but i think the demo doesnt let you play with anyone? I would appreciate a bit of help
The Demo is designed to be given to a second player. So if you have the full game, someone with the demo can still join any match you create, they just can't create matches themselves. It's supposed to encourage people to share it with a friend so they can see what the combat is like without the second player having to purchase anything.
Were you having connection issues?