I'm a bit confused about the API change required here:
Is it telling me I need to stop using inventoryQuantity, inventoryQuantityAdjustment, and restock fields when I get variants.json? Or do I need to add location_id to all my fulfilment and refund requests, of which my app does none. Is there a tool that can help me find what's triggering the error or a method I can use to traceback?
Any chance you’re using the Shopify_app or shopify_api gems with rails? I had this same message and upgrading my api version to a more recent version helped. After that, I moved the fulfillment management info for a variant into the variant collection before saving the product. Before, I was updating the fulfillment service info after the variants were saved, which you can’t do anymore.