Unable to close July period on Payables

Hello team,

I am unable to close July period on payables. I discovered that this is as a result of some transactions that have not been accounted for. I generated the period exceptions report and also unaccounted invoices and i got a number of invoices. I searched for some of these invoices and i saw that they've been cancelled. My observation is they are taxes that were cancelled from parent invoices. How do i locate the parent invoice? i need to locate the parent invoices to the attachment i will send along with this request. Your prompt response will be appreciated.