Thanks, Claire, and sorry for the delay getting back to you; I was away last week and all posts in the feature request section fall under my remit!
Unfortunately, Square make this impossible for us. When you refund an order in Square, they create a brand new “order” for a negative value and don’t give us any information to link this to the original. They’re just completely separate transactions that both relate to the same customer, so we create these as credit notes in Breww, but have no way of knowing that it should be applied to a previous invoice.
If the refunds are typically same-day, then this may be “fixed” by Square, Zettle & other POS integrations to have a daily/weekly/monthly invoice as both transactions would be grouped together. If you think this would help you, please give that thread a vote.
Thanks and I’m sorry I don’t have a better answer for you.