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Solution: Accounts Payable GL Account can be changed using Mutual Settlement Document.
1. Suppose that you have there is unpaid Invoice Received from Company ABC with CR balance on BS Current Trade Payables:
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At Accounts Payable tab, select unpaid Invoice Received:
At Payee Attributes Tab, sSelect select the Contract, open GL Account settings and select the new GL account in Accounts Payable field:
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