Red buff Health Bug-gameplay

So the enemy team and mine were fighting near red buff and we did some damage to the red buff while we were fighting then then everyone left to heal up when i came back to the red buff its health didn't reset to like 2000 instead it was just at 800 or something. No one was near it when i came back it was sitting in place and we had wards around the map to tell us if someone would have came near.