Melee Minion Bug

There is a current bug with melee minions that is happening quite frequently as of late. It seems 1 of the three melee minions tend to freeze in place, it cannot attack and constantly moves back in forth in place. It think its a castor when its a melee. I dont know how its reproduced but i it happens when a melee gets close to the castors. Have any of you noticed this bug?