I am no longer receiving email notifications for any messages/comments. I have not changed my notification setting and don’t understand why this happened. 

Did you download the app?

I did and it didn’t work either. Both the site and app. 

If you downloaded the app, then it will disable the email notifications by default.

I deleted app. Still no email notifications . This happened before I downloaded the app

is there a way to stop notifications from watched topics while keeping notifications for messages on profiles, feeds, replies and quotes?

It's the opposite for me. I keep receiving emails and notifications even when I opted out of all of it.