The primary way to start troubleshooting this issue is with some speed tests using this protocol. However, the following two things should be checked first...
1. On the Home page of the modem's System Control Center (click the link), does it show that you have Service Plan Data or does it show that you are out? You may need to click "Home" on the left of the page to show your data levels.
2. When checking this modem page, what do you see for the State Code, which is listed in the System Summary box near the top of the page?
We're closing this thread since we never got a reply from you. If you still have concerns, please start a new thread and include a detailed explanation so we can more effectively help you.