More infor please. New hives, whether from swarms or packages, work hard and heavy from the get go so a lot of activity is not a major concern. In robbing look for bees landing on the sides of the box or above the entrance, hesitating, and then dashing in. The other thing to check is for bees flying back and forth between hives. With new hives when all are being fed it is possible for a round robin of robbing to develop. Any fighting on the landing boards?
Observe and report back and we can give you better answers.