I am trying to cancel a line on a BPA and I get the error 'Error:Line # You cannot finally close thi

Dear Friends,

Question: Can we cancel lines on a BPA? Under what circumstances?

What we are trying to do, is find out lines which were billed for the ordered quantity but not all of these have been received. I know and tried on a standard PO and this works ok, but with the BPA it throws this error.

'Error:Line # You cannot finally close this line because open releases exist.'

On the standard po, the issue preventing me to cancel lines was the 3 Way match approval level. I changed this to two way and it allowed me to cancel lines. But on a BPA there are no shipments. So how do I cancel the lines where the received quantity is less than the billed quantity?