If you have incorrectly invoiced out a line or WIP.
File, History, Locate the invoice number and double click the line:
A prompt should then ask you if you wish to return the parts back to stock:
After this, select Action to print the credit note.
Partial Credit Note
If that does not work and there are multiple invoices on a WIP for multiple accounts, you will not able to do a full credit. In this case, you need to change the account to the same account you used on the invoice.
Right-click on the status of the lines that you want to credit to change it from X to C.
Then click Action and select Partial Credit.
*** edits by ST 10/11/2023