Requisition personalization

Hi

i need help on creating a form personalization.

I have one Legal entity with 5 OU. Each operating unit has its own inventory organization.

We are going to use Core Purchasing in the 5 OU. Using Requisition form.

Only Expense. We don't use Inventory, nor inventory items.

Right now, when I create a Requisition on Requisition form, after the line, there is destination (will be always Expense), then requester and then Organization. The field Organization is mandatory and it is empty. When I click on LOV, I see the 5 inventory organization.

I need to see or fill by default just the inventory organization related to my OU.