I get this issue once in a while and don't know if I'm doing something wrong or it's an actual problem regarding the power, but once I relog, I'm able to do my combo without an issue (which is only a temporary fix, after a while I have the same problem again)
I'm having exactly the same issue, and that's really bad because I run PoD and it becomes useless without the group heal.
I've had the same issue. From what I can tell, the bug happens when I join an instance and use the armory to switch to my healer build to "quickly". What i've started to do now is wait 15 or 20 seconds after joining an instance before switching to my healer armory build. Haven't seen the bug since i've started to that.