How to Modify a 1099 Code on Paid Invoice

How do I modify a 1099 code on a posted invoice?

1099 Processing

1. Go To Modify Invoices
2. Pull up the invoice in question
3. Select Invoice Detail > Update
4. Use the drop down on the 1099 column to change the code

1. Go to Vendor 1099 Detail
2. Search for the Vendor number and 1099 year
3. (Mass) Delete record(s) to remove one record or all records in the find set

New to Functionality

Need Accounts Payable Permission to Modify 1099 Codes. Otherwise the drop down will not work.