Closing Goods Receipt POs 
When you close a goods receipt PO, no adjustment posting is carried out in inventory management. This means that the available inventory, which has been increased by the goods receipt PO, will not be reduced again.
Therefore, if you need to close a goods receipt PO and have the inventory values and quantities updated as well, create a goods return based on the goods receipt PO to be closed.
Note
After you have closed a goods receipt PO, you can no longer base other purchasing documents on that goods receipt PO.
Prerequisites
The goods receipt PO has not yet been copied to an A/P invoice or a goods return.
Procedure
From the SAP Business One Main Menu, choose
Purchasing – A/P 
Goods Receipt PO 
and select the relevant document.In the menu bar, choose
Data Close .You receive a message: Closing a document is irreversible. Document status will be changed to “Closed” and a clearing transaction will be created. Do you want to continue?
Do one of the following:
To proceed and close the goods receipt PO, choose the Yes button.
NoteIf you are running a non-perpetual inventory company, the goods receipt PO is closed and the document status is changed to Closed.
If you are running a perpetual inventory company, proceed to step 4 to specify the posting date for the clearing journal entry.
End of the note.To cancel the operation, choose the No button.
If you confirm that you want to close the goods receipt PO, a dialogue box appears asking you to specify a posting date to be used in the clearing journal entry. Do one of the following:
To use the current system date, select the Current System Date radio button.
To use the original posting date in the document, select the Original Document Date radio button.
To specify a date other than the above two dates, select the Specified Date radio button, and then either enter a date or choose a date from the calendar.
If you specify a date that is earlier than or the same as the original posting date of this document, you receive the message: Enter a specified date that is later than original document posting date.
If you specify a date that is in a locked period, you receive the message: Period is locked for new data. For more information, see Locking Posting Periods.
To save the data, choose the OK button.
NoteWhen a goods receipt PO (either fully or partially drawn) is closed, the amount of Freight posted to the expense account and not drawn into an A/P invoice or a goods return is cleared.
End of the note.