AFS Grid value problem

Hello,

After i create a sales order in va01, and want to change the quantity in va02 tcode. I select AFS ITEM and edit the quanity, after i save it and again enter using va02, in the grid value i.e., matrix entry all the items i entered is missing. And most of the times the quanitiy is doubling. i.e., if 500 units of shirts were entered in va01, here automatically it doubles. My client is facing this problem. Is there a SAP PATCH error??

Thanks in Advance.