I updated EA to 3.4.8 and Polylang to 3.03 and it works
Hello,
I had the same issue.
I turned off all plugins and re-enabled EA. That worked.
I turned on, one by one and for me it came out that the Polylang (3.0.2) plugin was the problem.
I do not need the Polylang (do not have the site translated yet) so I kept it disabled.
It is now working as it should be like before. Although I had to change all the email settings while they were gone.