Data/WiFi issue

I can’t play on any sever with data. At this point I’m getting tired of it, I have all the requirements to be able to play with data like I have on the use cellular data and the multiplayer on as well but every time I try to join a sever it says you must be connected to with to be able to play with friends. I watched tons of videos and I have everything done to able to play but it still won’t let me. And apparently I’m not the only one with this problem.