No, it happens randomly, for a while I thought it was me pressing buttons by mistake on my phone but it has happened pretty randomly a few times even after taking little breaks on steemit, I read on a Witness once it happened sometimes, don't ask me why. I'm glad I kind of check "manually" sometimes, it would be nice to know "when" I unfollowed on the first place XD just to be aware... but I swear it happens always on offline or sleeping times so unless sleepwalking I cannot make sense of it, Either way, fixed :) XD