Behavior Tree MoveTo doesn't finish before leaving

Not sure if this is a bug – using Behavior Tree I have a simple Sequence set up where a BT Task randomly gets a waypoint, then MoveTo task is called. It works fine for a while, then at some seemingly random point in time, both tasks are called repeatedly and rapidly before the MoveTo completes, bouncing between the tasks. causing the pawn to stop. I’m not sure if I’m doing something wrong or something is happening that I don’t understand.

It doesn’t seem to be triggered by anything in particular, sometimes it happens sooner rather than later.

Any ideas on what might be happening?