Refund - How to

[Patricia VanBuren]

Hello,

I am using GnuCash for my small business and have a question regarding how
to process a refund.

I sold 2 items ($75 and $83) and invoiced my customer for a total of $158.
I received 2 payments: ($50 and $108) and the invoice was paid in full.

I now want to correct the invoice to reflect that I am giving away one of
the items (100% discount) and need to refund $75 but don't seem to find a
place where to enter that amount now that the original invoice has been
paid in full.

Do you have any documentation on how to process a refund?

THANKS!