Hello, ed4blue50! Thank you for reaching out to us. If you have our modem that supports xFi feature, you can create different profiles, assign devices to those profiles and see how much data each profile uses. As of now, we don't have a feature that will show how much data each device use.
If you think that the data usage meter is incorrect, please reach out to our Customer Assurance Team at 1-877-807-6581 (Hours of Operation: 6:00 AM - 2:00 AM ET/Seven days a week)