Limbo (Prime) Passive not working.

[(PSN)DaGrimsRawState]

So I understand Limbo is not a very liked frame. But I tend to switch between frames every so often as to keep the game fresh for myself. However, there are times where frames do outshine in certain situations. In this case, Limbo, for a Riven Defense with no damage. And Normally this wouldn't would be as difficult to maintain, spamming and killing all enemies and refresh my bubble size as to not let them get near the objective if I can get my 10 energy per kill as his passive says. I noticed this in-game and thought maybe its a one time bug but it isn't. To me this feels as though he is useless as his most used powers (Stasis and Cataclysm) cannot be repeatedly used with the help of his passive.