At the moment we are facing issues with partial refunds in combination with the correct VAT. Sometimes we want to provide a discount to a customer after an order has been placed (as we can't apply multiple discount at once). However, issues show up if we want to refund the customer partially, as no VAT would be applied over the refund.
For example: Customer Y buys three items of our store with 21% VAT with a total value of €50 incl. VAT. A discount code of 5 euro's was not applied, and we now want to refund the 5 euro's to the customer correctly with VAT (so 4.13 revenue refund, and 0.87 VAT refund). However, if we would just refund 5 euro's without selecting any items, then no VAT would be refunded (so €5 revenue refund, and €0 VAT refund). If we would select an item of this order sold for let's say €20 euro incl. VAT and then refund 5 euro's of the item, the tax reporting seems to show the following (3.47 VAT refund (VAT refund over the full item), €1.53 revenue refund (leftover amount of the 5 euro total refund).
So how should we refund the 5 euro discount correctly with VAT reporting? Our invoices are created automatically based on the data in Shopify, so right now all credit notes are processed incorrectly.