In order to copy these items, Copy the billing cycle (BB711008) with which they are associated.

Or

Edit the Billing Item to reflect specific dates, rather than a Billing Cycle:
  1. Open the Billing Item
  2. Remove the Billing Cycle from the Dates field and select Item can only be used from, enter desired dates.
  3. Copy the Billing Item (BB230265)
If the item is still missing to copy, it could be marked as Inactive:
  1. In Products and Billing Items, click Filters
  2. Mark the box to Show inactive items
  3. Open the Billing item
  4. Change the status from Inactive to Active
  5. Save and close the item
  6. Copy the Billing Item
Or

If you are copying a minimal number of items, you can create new Product and billing items.(BB202965)