Remove Intercompany Allocation (B/U)

Summary:

We have a business that we have recently sold that was setup in our intercompany configuration to trade between our businesses. This issue now is that, we've un-ticked the enabled for Intercompany in the Intercompany Org setup screen and changed Customer/Supplier association screen but when our parent company now inputs an AP invoice from the business that we've sold, upon creating the accounting it shows our intercompany account segment instead of the regular trade creditors account.

How do we stop Fusion from recognising AP invoices between these two B/U's as intercompany?

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