I've been going through the process of restarting, disconnecting from Facebook and reinstalling and none of this is fixing my activity feed. I figure I'll just have to wait it out at this point for a Spotify empolyee to post a fix, but it seems like this has been an open issue for a lot of folks.
I love Spotify and will always be an adovacte, but this feels like a problem they're overdue in fixing.
The service issues of the last couple of days affected the activity feed for a lot of people but everything should now be back to normal. It is possible that it may take a while for everyone to catch up.
However, some users have been having problems with their activity feed for almost a year. Sometimes relogging gets it going. Spotify is aware of this issue and is trying to identify what might be causing this.