[Boards] Thread History Deleted?

For some reason, my past discussions shown in the "My Discussions" tab of my profile have all disappeared , but they can still be accessed with a link.

This thread:http://boards.na.leagueoflegends.com/en/c/miscellaneous/ZrsnA4Qd-possible-solution-for-champ-select-trolls-dodge-cards-and-report exists, but isn't in my history

The owner of the unprepared garen thread lost it in his history also, but was still accessible from a link http://boards.na.leagueoflegends.com/en/c/site-feedback/UEh3mc1O-im-having-a-little-panic-attack-cant-find-my-unprepared-garen-thread?

Bug?