Sage 50 US

How do I get a voided check to not go back in as an unpaid invoice? or how do I get rid of an invoice in the previous month without messing up my closed month that has already been reported on? I can't just go back into the previous month and change that…

I had to create duplicate sales invoices and then voided out the originals. I used the wrong date when I voided them and now I need to change the date or delete the invoices all together. How do I do that?