unable to modify the distribution lines

Hi,everyone.

I have some problems in AP prepayment invoice.

The user made some manual changes to this prepayment invoice.He canceled the lines, and then he added one positive distribution in the canceled distribution lines.So,there is a mismatch in case of distribution lines and header/lines amount and hence a hold is placed when validation was done.The invoice header amount is 0, and the invoice line amout is also 0.The current status of the invoice is "needs revalidation".on distributions page, everything is greyed out.

Please suggest how can we modify the distribution lines, so that we can remove the hold and proceed with the validation of invoice.There is not something related to the responsibiliy.