We often have to edit the value of the tax on AP invoices by a few cents (due to rounding errors) before they are in balance and can be posted.
 
This is done in edit General Ledger Batch Entries (GL-P)
 
The Invoice # always used to show as the actual invoice number but at some point started being some other reference number starting with #  not sure where it came from but always consistent for any one AP invoice. (Still shows the WO number for works orders, etc)
 
The problem is when editing the cents on the tax it changes the reference on that line to the actual invoice number, so it no longer matches the # number on the rest of the lines for that invoice and is therefore "out of balance" and won't post.
 
Going back in to change the reference to the # number should work, but then instead of either the invoice number or the original # number it assigns a new reference number (it does this in sequence for changes so it must be getting the starting number from somewhere).
 
Also it doesn't seem to do it consistently - one day editing the cents was no problem the next it does this. Same again a week or so later.
 
Can fix it by changing the reference to the correct one in the tables in maintain database and then it posts fine, but why is it doing it and how do we stop it doing it again?
 
 
Haven't made changes or updated in ages so just want to know why?