Only do one or the other , not both Seen and Stop Following.
Click on Seen and it clears the posting immediately, but it returns next time you look in.
Click on Stop Following and then on Ok and wait until you get a message confirming the choice before doing anything else.

It will as soon as someone else comments if you mark seen, if you mark stop following they should go forever, but only when you visit Goy again I find, try logging off then on again, that may help....if not I,d contact admin.

Its frustrating that you can only delete one at a time though - anybody know if you can delete a whole lot at once?

You can delete about 3 at a time. Just do Stop Following and Ok, then quickly do it to the next one on the list and quickly on to the third one. Works for me.

Wow, will give that a try!