Why is a refunded item still showing as owed in POS?

[Louise_Lee]

A customer bought some items at our POS, they paid in cash.

They then did not need one of the items.  I refunded this on the system and gave them the cash back for the item.

Shopify still shows this as customer owes £9 for the returned item.  How did this not close off when the item was refunded on the POS.  What am I doing wrong?  

[HKJ]

It looks like you only accepted £56.80 to begin with.