Phantoms only attack once, then permanently hover until they despawn

I am seeing this bug again in the latest update, 1.16.20 I think it is. When phantoms first spawn, they attack once immediately. But after the first attack, they then go into permanent hover. They feign diving again, appearing to dive down a few blocks, but then pull out of the dive and go back to hovering again. I am seeing this on the Xbox One.