Why do I receive the error: Quantity exceeds the quantity limit! when trying to update the quantity on an invoice?

This error appears when the Purchase Order (PO) is in Partially Invoiced status. The line item was only created for quantity 1, which has already been invoiced, therefore the line item is closed for invoicing. 

Contact the Buyer to either update the Purchase order with the proper quantity for invoicing or to enable the rule Allow suppliers to increase item quantities on invoices in order for you to update the quantity.

Additionally, if you are able to adjust the quantity field and price field a decimal can sometimes be used in order to bypass the error message and successfully submit the invoice with the correct subtotal. 

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