SCFO Global Procurement Flow not getting triggered

Summary:

We're trying to Create a Procurement Flow with below details

China BU as Procurement BU

Singapore BU as Requisition BU

We made the setups and tried to create a PO with Procurement BU as China and Requisitioning BU as Singapore. We're unable to change the Bill to BU and Sold to Legal Entity other than Singapore. We need China as bill to BU. We have created a custom role for privilege (PO_OVERRIDE_PO_SOLD_TO_LEGAL_ENTITY_PRIV)

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