I was following a profile a long time ago. I have since tried to unfollow their profile, but it still appears in my activity feed.

I have followed again, then unfollowed again, to hopefully solve the issue. No effect

I then blocked them, but they still appear in my activity feed.

I then cleared the Steam cache, but the profile still appears in my activity feed.

I have contacted Steam support, but they insist that they cannot help either.

What on earth is going on? Am I doomed to forever see their content on my activity feed?
Any help to get rid of their stuff on my activity feed would be much appreciated