Solution:
i erased the local data for the game and voila, it fixed it now i can play online normally (erasing your local data wont make you lose progress in the game) as long as you don't erase the data on the cloud you should be fine.
also i don't know wether this is a permanent solution or you will need to do this every time you start the game.
edit 2: nevermind it still freezes, it only works sometimes for some reason, why won't ea just patch the damn game?
>go to manage game ans add ons
> go to saves
>go to your save and press delete local
that's it, that fixes it
honestly i don't understand how deleting a local save fixes not being able to play online but oh well, there it is.
PD: EA you bunch of incompetent people , you used to be good before 2014
PD2: remaster burnout 3 goddamit are you afraid of money or what?
edit: after hours of testing i think i finally cracked it ! do all of what i just said plus clear your persistent blu ray storage
go to settings, blu ray and then persistent storage , clear it and you're set, that will get it to work as it should (for some reason).