credit memo invoice linked to a standard invoice.

hi all

one of our user has had a problem with an invoice that is put on hold by the system and the hold name is Line variance as the invoice line amount is not equal to the invoice amount.

the are 5 lines on the invoice and all the lines amount is 0 and the invoice amount is 124.000

the user did a credit memo on the invoice but the specific standard invoice is now manualy approved and on the status of needs revalidation.

i need to ask if i update the invoice amount to be the same as the lines and revalidate the invoice then cancel the invoice will it affects the credit memo ? or i have to also cancel the credit memo allocated to the standard invoice?