I've got the same problem.
I followed the troubleshooting steps and found that I have 1 EA account linked to 1 active ps4 account and 1 inactive ps4 account. However I have no idea if this is causing the problem.
I currently have an active ps + sub and I've played different games online through ps +. BF1 seems to be the only game with connectivity problems.
Please fix this issue ASAP.
