Unsuspend Client Account
From Lunarpages Web Hosting Wiki
To unsuspend a client's account in WHM you can go to Account Information > List Suspended accounts
Then click the Unsuspend button for the account.
Alternatively you can go to Account Functions > Suspend/Unsupend an Account
Click on the suspended account highlighted in red then click the Unsuspend button.
This will restore full access to the account.