I am really confused about this too. I have been on Gen 5 for a few days and trying to get usage to understand how to manage usage. Now I find they are resetting daily. I don't mind the "free" data but Hughes seems to be hiding the actual usage. Why? This is when I am trying to evaluate the service. If they are hiding something that is misrepresentation. The honest way to do this is to report the usage and at the end of 20 days give a credit for that useage and indicate a courtesey.
In the first month I am evaluating the service and part of the service is the usage meters. They are not working correctly if they are being reset every day. They are misrepresenting what is actually happening.
You should have received A "Welcome to HughesNet" email that among other things explained that your usage will re-set daily for the first 20 days of service.
This is not done to hide or confuse but to allow new users a chance to update all their networked devices with impacting their first month usage.
Hughes supplies a number of usage as well as history meters as an aid to users tracking their data usage.
I suggest that even though the post as the following link is a work in progress that you read it carefully as it describes all of the tools available to you:
While the "usage" meters will re-set daily, the "history" meters will not so that will show your daily totals.