Final delivery not entered for the order. It is not technically completed

What causes this issue?

If you want to settle a production order to a material, you must first
either enter the final delivery for it, or close (complete) it
technically because settlement leads to an update of the moving average
price for the material. The total delivery quantity is required for
this. If the order is one which cannot be delivered because, for
example, it produces 100% scrap, you can close it technically instead.
Settlement is than to the price difference account.
By the settlement period, no final delivery had been entered for this
order, nor had it been technically closed (completed). This means that
you cannot settle it.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Before settling, either set the order to "Technically completed" or
enter the final delivery.

Error message extract from SAP system. Copyright SAP SE.