I tried it on a live client store which is located in Germany. The merchant has the unit prices setup and configured. Same error that I got on the dev store.
When the dev store was configured to be in a different country, the option was not available. It’s only available after switching to Germany, inline with what is said here: https://help.shopify.com/en/manual/intro-to-shopify/initial-setup/sell-in-germany/price-per-unit
Who should I contact to check whether this API can be “turned on”, if it needs to be?
Thanks.