Hi Mehdi Adinkra, 

When selecting the receipt, you are not seeing the gross price of the receipt on the invoice?

If you see the quantity not flowing thru, then check the PIHQTYAQR parameter under ACH/INV.

Do you have any customizations in purchasing module?

thank you for your help , the quantity was the first thing i checked but it appears at the invoice , the parameter allows both the status A & Q , however it is only the price that doesn't appear on the invoice and therefore the amount , and like i said the problem seems to be  related to one particular article.