Note: You cannot set a cancelation date to a date that has already been billed.
Note: If you need to cancel multiple account-packages see the 'Bulk Operations/Transferring/Canceling Multiple Account Packages' guide.
Select the account-package you wish to cancel in the list on the left under the Account Packages heading
On the right under the Edit Account Packages heading enter a date in the Effective Cancel Date field
Click Save and the package will be canceled when billing occurs and the period being billed falls within the effective cancel date provided.