"Unable to connect to the world"

Good evening.

A few days ago and even today, I (Xbox one) and a friend of mine (play station 4) are trying to play together but it gives us a screen that says "Unable to connect to the world", both if I try to enter the his world is if he tries to enter mine. I tried to put both friends of friends and just friends on my microsoft account settings, but can't log in. He invited me into a creative world that he was already using on his own but we didn't even succeed in that way.