Limited performance due to missing value: GTIN

You submitted products without a GTIN in a category where manufacturers normally assign one. This is a limited-performance warning, not a disapproval — the products still serve, but with reduced visibility, because Google can't match them to its product catalog as precisely.

Common causes

• ·The GTIN/barcode field isn't mapped from the shop system into the feed
• ·Products genuinely have manufacturer barcodes, but they were never entered into the shop data
• ·Custom or handmade goods without a GTIN that aren't marked accordingly

How to fix it

1. 01Fill the gtin attribute with the manufacturer-assigned barcode (EAN/UPC/ISBN) wherever one exists
2. 02Make sure the value isn't from a restricted range (e.g. internal or coupon ranges)
3. 03For products that truly have no GTIN, set identifier_exists to false — only where that's actually true
4. 04Re-upload and confirm the warning clears in the 'Needs attention' tab

Checked against Google's documentation: Google Help