AP quantity transfer to PA

Hi all,

I created one credit memo in AP match to return to supplier business in PO, the quantity is -3000, the amount is $-3000;

After I transferred this into PA, what I found is the amount $-3000 is transferred into PA, but the quantity -3000 didn't transferred into PA, the quantity changed into 0 to PA.

I don't know why ? Waiting for your reply

Thanks