When you process customer receipts for payments sometimes they might not pay a full invoices. This could be because they were expecting a credit and that hasn’t been entered in your system yet. They were taking a promotional discount ahead of when it was processed in your system. They are taking money off for a late delivery or some other penalty.
They are sometimes annoying amounts that you have to reconciled somewhere or park until you can reconcile and process layer. There is a feature called deductions that you can use to handle there.
Here is a quick overview.
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