Invoice cancelled but associated WHT invoice not cancelled

Hello all,

Have a quick question for the payables community. I have a query from a user about an invoice she had cancelled. Now this supplier has been attached with a Withholding Tax Code so when the invoice was initially created, the Tax Code was correctly applied and 10% was shown on the invoice header as 'Withheld Amount'

Subsequently, she cancelled the invoice. However, the withheld amount is not cancelled and it still appears in the Trial Balance. The distribution total on the original invoice doesn't show a violation nor does an unpaid WHT invoice appear as payable to the Tax Authority.