There are additional problems as well, not sure if related or not.

After we have posted new AP transaction entries under the correct Vendor, when we go to print checks and the Invoice Selection screen, for some reason some invoices/transactions have spontaneously changed their vendor IDs. I double check the entry and it is entered correctly but when I go to invoice selection, it shows up under a different vendor ID (I am selecting transactions based on due date). It seems to duplicate the entry if the $ value is the same, even though it should be different vendors. This is a HUGE problem and we need help ASAP as we can no longer cut any AP checks. I am just hoping this doesnt affect payroll processing... 

Please see below screenshots. The ones marked in red for some reason duplicated themselves, even though they should be entirely different vendor IDs for those 3 transactions