New user question! Apologies if this has been covered. I have an existing brick & mortar business and just today turned on our Shopify POS terminals. Super excited to move into the 21st century. All seems to be going well so far, however we had a return from a transaction last week and there doesn't seem to be an obvious way to process a return from a previous system on a Shopify POS. The old system was a glorified adding machine, so there isn't a 'record' of the transaction beyond the receipt. Is there a way to issue a credit, refund, or cash for a transaction that was not done on a Shopify POS?