After PO Rollover, cannot cancel distribution line

After the PO rollover, the remaining quantity of a distribution line needs to be canceled. There are two distribution lines;

Distr Line 1: For the prior year, is closed, and shows a partial received quantity/amt.

Distr Line 2: For the current fiscal year, is open, and shows the remaining quantity/amt. 

The user tries to adjust or cancel Distribution line 2 because the items will not be recieved. A message displays "XX has already been received against this distribution (10200,89) This distribution has been at least partially received already. Therefore, you cannot change the distribution quantity to be less than the received quantity, nor can you delete or cancel the distribution."