Scenario
Edit Customer in Journal with status “Approved for Posting Payments Applied”
Solution
The reason why user is not able to edit the Customer on the transaction line of the Journal is because it is applied to the Payment transaction.
To be able to resolve this, user needs to unapply the Journal in the Payment by editing the Payment record and uncheck the checkbox in the Applied to subtab of Apply tab.
Upon saving the Payment record, theJournal should have a status of Approved for Posting instead of Approved for Posting Payments Applied. Furthermore, Customer field should not be grayed out when the Journal is edited.