This is applicable only if you have Plesk VPS or Plesk Dedicated Server with you.
1. Login to your Plesk Server account.
2. Click "Resellers"
3. Click on the "Reseller Name" which you want to unsuspend.
4. Middle-click "View More Statistics" to view the oversusages reasons shown in "Red" color on next screen
5. Click "Activate" to unsuspend the reseller ac.