One of the accounts on my server has passed its bandwidth for this month; as the result, the account has been suspended. I got a system email saying that this account will be suspended for the rest of the month. However, I have change the package for this account to have more bandwidth, and I also unsuspended the account. On DA, it shows that the account is no longer suspended, but if I go to the website homepage, the suspended message still shows up on its homepage. On the other hand, the site displays as normal if I go to all other pages
From the Original Post it appears as he has DA (Direct Admin). Have you checked your .htaccess file? Maybe this is still pointing to the suspended site page.
If you use IE, you may be pulling the site from cache instead of the server. If you hold down the CTRL key and hit the Refresh button, it will get the latest version from the server, and ignore any local cache.