Drought I should think, especially if it's still recovering from being moved.
You may be able to save it with a good drenching and then keep it watered but not sodden until you see signs of recovery.
When a perennial plant is stressed, the first thing it does is sacrifice flowers. Camellias make theirs form late summer and must never be allowed to dry out from then until late autumn or they will drop their buds so if yours does recover, give it some liquid tomato food in with its drinks and some slow release blood, fish and bone or rose food.