I have had challenges with the same problem with VAT code but also EAN that we use in DK.
I’ve solved this by creating a Meta field and then adding this code in cart.lic, that is, on the Cart page:
It has worked flawlessly until last week when it stopped. The data that the customer enters in the field will not be stored.
Has anyone experienced the same problem? Have there been changes at Shopify that make the code no longer work?
I’ve had a dialogue going on with Shopify support, but they won’t help with anything when code is included in the problem.
//Mik