The sales order invoicing process has a functionality where the end user could identify a particular quantity which will be invoiced, and this could be controlled by the over/under deliver percentage on the sales line. The invoiced quantity in the sales order invoice is linked to the item
unit of measure, where the item inventory unit of measure could be different than the sales unit of measure. For example a company stock specific item in Kilogram and sell it to the end customer in Ton, in that sense the sales invoice will be issued in tons, and the inventory consumption will be in kilogram and bear in mind that in some scenarios the inventory and sales unit of measure are the same.
The unit of measures are defined on the item master, Product information management| Common| Released product, then press edit on a particular item record then go to Manage costs fast tab, as shown in the below screen shot the which illustrate the inventory base unit of measure.
In order identify the sales unit of measure move to Sell fast tab
In a sales order with quantity = 10 ea in a sales line, the quantity here represented in the sales unit of measure.
The quantity of the sales line which represents the sales unit of measure will be reflected in the sales order invoice, in addition to inventory unit of measure as well. The quantity in sales unit of measure will be found under Lines tab, Update filed. The quantity under update will be the base of the revenue entry (Quantity * Sales price).
The quantity in inventory unit of measure will be found under Line details tab, Update filed. The quantity under update will be the base of the COGS entry (Quantity * Cost price).
If the user change the quantity in the update filed under the Lines tab, then the quantity under the Line details will be changed as well, if the user change the quantity in the update filed under Line details the quantities under Lines tab will not change, in that said the changes mechanism only works in one way as mentioned.
If the second scenario of changes occurred where the user change quantities under Lines detail, the system will keep the quantity under Lines tab as it represents the sales unit of measure, which is acceptable if there is a slight differences in the sales unit of measure and
inventory unit of measure.
But if it is occurred without a business requirement this will lead to inconsistency between quantity in sales order and quantity in inventory transaction.
And in other hand the generated financial entry of the invoice.
The conclusion an issue may raise because of this mismatch, and in order to check the posted transactions, go to Accounts receivable| Inquiry| History| Invoice then right click and press Record info, and press Show all fields.
The quantity in the left side represents quantity in sales line, and quantity in right side represents the quantity updated in the inventory transactions.
The rationale behind it in case there is an item has two different unit of measure (Sales & Inventory) and the user may want to change the quantity of which will be reduced from the inventory without changing the quantity in the sales order, in the other hand if the item has the same unit of measure the quantities in the two fields should be identical, but if the user changes the quantities under line details tab it will not change the quantities under lines tab. Please note that the same mechanism working in the Purchase order side.