Hello, I've managed to use the PUT and POST requests to add metafields to my customers. However, after the initial insertion of the data, i cannot update the metafields because i need to pass the ID of the metafield to update. However, I can't get the actually metafields using the shopify API.
You never get metafield resources when you request a parent resource like a customer, product or variant. You have to request them with a separate API call. So when you request a customer resource you can subsequently request the metafield resources attached to it. Try that and you'll see your metafields using API calls.
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